Dual-acting antihypertensive agents

ABSTRACT

The invention is directed to compounds of formula I: 
                         
wherein Ar, r, R 3 , X, and R 5-7  are as defined in the specification, and pharmaceutically acceptable salts thereof. The compounds of formula I have AT 1  receptor antagonist activity and neprilysin inhibition activity. The invention is also directed to pharmaceutical compositions comprising such compounds; methods of using such compounds; and a process and intermediates for preparing such compounds.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.60/899,264, filed on Feb. 2, 2007 and No. 60/901,531, filed on Feb. 15,2007; the entire disclosures of which are incorporated herein byreference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to novel compounds having angiotensin IItype 1 (AT₁) receptor antagonist activity and neprilysin-inhibitionactivity. The invention also relates to pharmaceutical compositionscomprising such compounds, processes and intermediates for preparingsuch compounds and methods of using such compounds to treat diseasessuch as hypertension.

2. State of the Art

The aim of antihypertensive therapy is to lower blood pressure andprevent hypertension-related complications such as myocardialinfarction, stroke, and renal disease. For patients with uncomplicatedhypertension (for example, no risk factors, target organ damage, orcardiovascular disease), it is hoped that reducing blood pressure willprevent development of cardiovascular and renal comorbidities,conditions that exist at the same time as the primary condition in thesame patient. For those patients with existing risk factors orcomorbidities, the therapeutic target is the slowing of comorbid diseaseprogression and reduced mortality.

Physicians generally prescribe pharmacological therapies for patientswhose blood pressure cannot be adequately controlled by dietary and/orlifestyle modifications. Commonly used therapeutic classes act topromote diuresis, adrenergic inhibition, or vasodilation. A combinationof drugs is often prescribed, depending upon what comorbidities arepresent.

There are five common drug classes used to treat hypertension:diuretics, which include thiazide and thiazide-like diuretics such ashydrochlorothiazide, loop diuretics such as furosemide, andpotassium-sparing diuretics such as triamterene; β₁ adrenergic receptorblockers such as metoprolol succinate and carvedilol; calcium channelblockers such as amlodipine; angiotensin-converting enzyme (ACE)inhibitors such as captopril, benazepril, enalapril, enalaprilat,lisinopril, quinapril, and ramipril; and AT₁ receptor antagonists, alsoknown as angiotensin II type 1 receptor blockers (ARBs), such ascandesartan cilexetil, eprosartan, irbesartan, losartan, olmesartanmedoxomil, telmisartan, and valsartan. Combinations of these drugs arealso administered, for example, a calcium channel blocker (amlodipine)and an ACE inhibitor (benazepril), or a diuretic (hydrochlorothiazide)and an ACE inhibitor (enalapril). All of these drugs, when usedappropriately, are effective in the treatment of hypertension. However,patient compliance remains an issue and physicians often prescribeagents on the basis of a benign side-effect profile, at the expense ofagents with similar or marginally improved efficacy. As a result, it isbelieved that only 50% of treated hypertensive patients achievesatisfactory blood pressure control.

In addition, each of the major classes of antihypertensive agents havesome drawbacks. Diuretics can adversely affect lipid and glucosemetabolism, and are associated with other side effects, includingorthostatic hypotension, hypokalemia, and hyperuricemia. Beta blockerscan cause fatigue, insomnia, and impotence; and some beta blockers canalso cause reduced cardiac output and bradycardia, which may beundesirable in some patient groups. Calcium channel blockers are widelyused but it is debatable as to how effectively these drugs reduce fataland nonfatal cardiac events relative to other drug classes. ACEinhibitors can cause coughing, and rarer side effects include rash,angioedema, hyperkalemia, and functional renal failure. AT₁ receptorantagonists are equally effective as ACE inhibitors but without the highprevalence of cough.

Neprilysin (neutral endopeptidase, EC 3.4.24.11) (NEP), is anendothelial membrane bound Zn²⁺ metallopeptidase found in many tissues,including the brain, kidney, lungs, gastrointestinal tract, heart, andperipheral vasculature. NEP is responsible for the degradation andinactivation of a number of vasoactive peptides, such as circulatingbradykinin and angiotensin peptides, as well as the natriureticpeptides, the latter of which have several effects includingvasodilation and diuresis. Thus, NEP plays an important role in bloodpressure homeostasis. NEP inhibitors have been studied as potentialtherapeutics, and include thiorphan, candoxatril, and candoxatrilat. Inaddition, compounds have also been designed that inhibit both NEP andACE, and include omapatrilat, gempatrilat, and sampatrilat. Referred toas vasopeptidase inhibitors, this class of compounds are described inRobl et al. (1999) Exp. Opin. Ther. Patents 9(12): 1665-1677.

There may be an opportunity to increase anti-hypertensive efficacy whencombining AT₁ receptor antagonism and NEP inhibition, as evidenced byAT₁ receptor antagonist/NEP inhibitor combinations described in WO9213564 to Darrow et al (Schering Corporation); US20030144215 to Ksanderet al.; Pu et al., Abstract presented at the Canadian CardiovascularCongress (October 2004); Gardiner et al. (2006) JPET 319:340-348; and WO2007/045663 (Novartis AG).

Recently, WO 2007/056546 (Novartis AG) has described complexes of an AT₁receptor antagonist and a NEP inhibitor, where an AT₁ receptorantagonist compound is non-covalently bound to a NEP inhibitor compound,or where the antagonist compound is linked to the inhibitor compound bya cation.

In spite of the advances in the art, there remains a need for a highlyefficacious monotherapy with multiple mechanisms of action leading tolevels of blood pressure control that can currently only be achievedwith combination therapy. Compounds having either AT₁ receptorantagonist or NEP inhibitory activity are known, but no single compoundhaving both AT₁ receptor antagonist and NEP inhibitory activity has beenreported. Thus, although various hypertensive agents are known, andadministered in various combinations, it would be highly desirable toprovide single compounds having both AT₁ receptor antagonist activityand NEP inhibition activity in the same molecule. Compounds possessingboth of these activities are expected to be particularly useful astherapeutic agents since they would exhibit antihypertensive activitythrough two independent modes of action while having single moleculepharmacokinetics.

In addition, such dual-acting compounds are also expected to haveutility to treat a variety of other diseases that can be treated byantagonizing the AT₁ receptor and/or inhibiting the NEP enzyme.

SUMMARY OF THE INVENTION

The present invention provides novel compounds that have been found topossess AT₁ receptor antagonist activity and neprilysin (NEP) enzymeinhibition activity. Accordingly, compounds of the invention areexpected to be useful and advantageous as therapeutic agents fortreating conditions such as hypertension and heart failure.

One aspect of the invention is directed to a compound of formula I:

wherein:

r is 0, 1 or 2;

Ar is an aryl group selected from:

R¹ is selected from —COOR^(1a), —NHSO₂R^(1b), —SO₂NHR^(1d), —SO₂OH,—C(O)NH—SO₂R^(1c), —P(O)(OH)₂, —CN, —O—CH(R^(1e))—COOH, tetrazol-5-yl,

R^(1a) is H, —C₁₋₆alkyl, —C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl,—C₃₋₇cycloalkyl, —CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,

R^(1aa) is —O—C₁₋₆alkyl, —O—C₃₋₇cycloalkyl, —NR^(1ab)R^(1ac), or—CH(NH₂)CH₂COOCH₃; R^(1ab) and R^(1ac) are independently selected fromH, —C₁₋₆alkyl, and benzyl, or are taken together as —(CH₂)₃₋₆—; R^(1b)is R^(1c) or —NHC(O)R^(1c); R^(1c) is —C₁₋₆alkyl,—C₀₋₆alkylene-O—R^(1ca), —C₁₋₅alkylene-NR^(1cb)R^(1cc), or—C₀₋₄alkylenearyl; R^(1ca) is H, —C₁₋₆alkyl, or—C₁₋₆alkylene-O—C₁₋₆alkyl; R^(1cb) and R^(1cc) are independentlyselected from H and —C₁₋₆alkyl, or are taken together as—(CH₂)₂—O—(CH₂)₂— or —(CH₂)₂—N[C(O)CH₃]—(CH₂)₂—; R^(1d) is H, R^(1c),—C(O)R^(1c), or —C(O)NHR^(1c); R^(1e) is —C₁₋₄alkyl or aryl;

R³ is selected from —C₁₋₁₀alkyl, —C₂₋₁₀alkenyl, —C₃₋₁₀alkynyl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, —C₂₋₃alkenylene-C₃₋₇cycloalkyl,—C₂₋₃alkynylene-C₃₋₇cycloalkyl,—C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b),—C₀₋₅alkylene-O—C₀₋₅alkylene-R^(3b),—C₁₋₅alkylene-S—C₁₋₅alkylene-R^(3b), and —C₀₋₃alkylenearyl; R^(3a) is H,—C₁₋₆alkyl, —C₃₋₇cycloalkyl, or —C₀₋₃alkylenearyl; and R^(3b) is H,—C₁₋₆alkyl, —C₃₋₇cycloalkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl, or aryl;

X is —C₁₋₁₂alkylene-, where at least one —CH₂— moiety in the alkylene isreplaced with a —NR^(4a)—C(O) or —C(O)—NR^(4a) moiety, where R^(4a) isselected from H, —OH, and —C₁₋₄alkyl;

R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d),—NH—C₀₋₁alkylene-P(O)(OR^(5e))₂, —C₀₋₃alkylene-P(O)OR^(5e)R^(5f),—C₀₋₂alkylene-CHR^(5g)—COOH and —C₀₋₃alkylene-C(O)NR^(5h)—CHR^(5i)—COOH;R^(5a) is H or —C(O)—R^(5aa); R^(5aa) is —C₁₋₆alkyl,—C₀₋₆alkylene-C₃₋₇cycloalkyl, —C₀₋₆alkylenearyl,—C₀₋₆alkyleneheteroaryl, —C₀₋₆alkylenemorpholine,—C₀₋₆alkylenepiperazine-CH₃, —CH(NH₂)-aa where aa is an amino acid sidechain, -2-pyrrolidine, —C₀₋₆alkylene-OR^(5ab), —O—C₀₋₆alkylenearyl,—C₁₋₂alkylene-OC(O)—C₁₋₆alkyl, —C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, or—O—C₁₋₂alkylene-OC(O)O—C₁₋₆alkyl; R^(5ab) is H or —C₁₋₆alkyl; R^(5b) isH, —OH, —OC(O)R^(5ba), —CH₂COOH, —O-benzyl, -pyridyl, or—OC(S)NR^(5bb)R^(5bc); R^(5ba) is —C₁₋₆alkyl, —OCH₂-aryl, —CH₂O-aryl, or—NR^(5bb)R^(5bc); R^(5bb) and R^(5bc) are independently selected from Hand —C₁₋₄alkyl; R^(5c) is H, —C₁₋₆alkyl, or —C(O)—R^(5ca); R^(5ca) is—C₁₋₆alkyl, —C₃₋₇cycloalkyl, aryl, or heteroaryl; R^(5d) is H,—C₁₋₄alkyl, —C₀₋₃alkylenearyl, —NR^(5da)R^(5db), —CH₂SH, or—O—C₁₋₆alkyl; R^(5da) and R^(5db) are independently selected from H and—C₁₋₄alkyl; R^(5e) is H, —C₁₋₆alkyl, —C₁₋₃alkylenearyl,—C₁₋₃alkyleneheteroaryl, —C₃₋₇cycloalkyl, —CH(CH₃)—O—C(O)R^(5ea),

R^(5ea) is —O—C₁₋₆alkyl, —O—C₃₋₇cycloalkyl, —NR^(5eb)R^(5ec), or—CH(NH₂)CH₂COOCH₃; R^(5eb) and R^(5ec) are independently selected fromH, —C₁₋₄alkyl, and —C₁₋₃alkylenearyl, or are taken together as—(CH₂)₃₋₆—; R^(5f) is H, —C₁₋₄alkyl, —C₀₋₃alkylenearyl,—C₁₋₃alkylene-NR^(5fa)R^(5fb), or—C₁₋₃alkylene(aryl)-C₀₋₃alkylene-NR^(5fa)R^(5fb); R^(5fa) and R^(5fb)are independently selected from H and —C₁₋₄alkyl; R^(5g) is H,—C₁₋₆alkyl, —C₁₋₃alkylenearyl, or —CH₂—O—(CH₂)₂—O—CH₃; R^(5h) is H or—C₁₋₄alkyl; and R^(5i) is H, —C₁₋₄alkyl, or —C₀₋₃alkylenearyl;

R⁶ is selected from —C₁₋₆alkyl, —CH₂—O—(CH₂)₂—O—CH₃,—C₁alkylene-O—C₁₋₆alkyl, —C₀₋₃alkylenearyl, —C₀₋₃alkyleneheteroaryl, and—C₀₋₃alkylene-C₃₋₇cycloalkyl; and

R⁷ is H or is taken together with R⁶ to form —C₃₋₈cycloalkyl;

wherein: each —CH₂— group in —(CH₂)_(r)— is optionally substituted with1 or 2 substituents independently selected from —C₁₋₄alkyl and fluoro;

each carbon atom in X is optionally substituted with one or more R^(4b)groups and one —CH₂— moiety in X may be replaced with a group selectedfrom —C₄₋₈cycloalkylene-, —CR^(4d)═CH—, and —CH═CR^(4d)—; wherein R^(4b)is selected from —C₀₋₅alkylene-COOR^(4c), —C₁₋₆alkyl,—C₀₋₁alkylene-CONH₂, —C₁₋₂alkylene-OH, —C₀₋₃alkylene-C₃₋₇cycloalkyl,1H-indol-3-yl, benzyl, and hydroxybenzyl, where R^(4c) is H or—C₁₋₄alkyl; and R^(4d) is selected from —CH₂-thiophene and phenyl;

each alkyl and each aryl in R¹, R³, R^(4a-4d), and R⁵⁻⁶ is optionallysubstituted with 1 to 7 fluoro atoms;

each ring in Ar and each aryl in R¹, R³, and R⁵⁻⁶ is optionallysubstituted with 1 to 3 substituents independently selected from —OH,—C₁₋₆alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl, —CN, halo, —O—C₁₋₆alkyl,—S—C₁₋₆alkyl, —S(O)—C₁₋₆alkyl, —S(O)₂—C₁₋₄alkyl, -phenyl, —NO₂, —NH₂,—NH—C₁₋₆alkyl and —N(C₁₋₆alkyl)₂, wherein each alkyl, alkenyl andalkynyl is optionally substituted with 1 to 5 fluoro atoms;

and pharmaceutically acceptable salts thereof.

Another aspect of the invention relates to pharmaceutical compositionscomprising a pharmaceutically acceptable carrier and a compound of theinvention. Such compositions may optionally contain other therapeuticactive agents such as diuretics, β₁ adrenergic receptor blockers,calcium channel blockers, angiotensin-converting enzyme inhibitors, AT₁receptor antagonists, neprilysin inhibitors, non-steroidalanti-inflammatory agents, prostaglandins, anti-lipid agents,anti-diabetic agents, anti-thrombotic agents, renin inhibitors,endothelin receptor antagonists, endothelin converting enzymeinhibitors, aldosterone antagonists, angiotensin-convertingenzyme/neprilysin inhibitors, vasopressin receptor antagonists, andcombinations thereof. Accordingly, in yet another aspect of theinvention, a pharmaceutical composition comprises a compound of theinvention, a second therapeutic agent, and a pharmaceutically acceptablecarrier. Another aspect of the invention pertains to a combination ofactive agents, comprising a compound of the invention and a secondtherapeutic agent. The compound of the invention can be formulatedtogether or separately from the additional agent(s). When formulatedseparately, a pharmaceutically acceptable carrier may be included withthe additional agent(s). Thus, yet another aspect of the inventionrelates to a combination of pharmaceutical compositions, the combinationcomprising: a first pharmaceutical composition comprising a compound ofthe invention and a first pharmaceutically acceptable carrier; and asecond pharmaceutical composition comprising a second therapeutic agentand a second pharmaceutically acceptable carrier. The invention alsorelates to a kit containing such pharmaceutical compositions, forexample where the first and second pharmaceutical compositions areseparate pharmaceutical compositions.

Compounds of the invention possess both AT₁ receptor antagonist activityand NEP enzyme inhibition activity, and are therefore expected to beuseful as therapeutic agents for treating patients suffering from adisease or disorder that is treated by antagonizing the AT₁ receptorand/or inhibiting the NEP enzyme. Thus, one aspect of the invention isdirected to a method of treating patients suffering from a disease ordisorder that is treated by antagonizing the AT₁ receptor and/orinhibiting the NEP enzyme, comprising administering to a patient atherapeutically effective amount of a compound having both AT₁receptor-antagonizing activity and NEP enzyme-inhibiting activity.Another aspect of the invention is directed to a method of treatinghypertension or heart failure, comprising administering to a patient atherapeutically effective amount of a compound having both AT₁receptor-antagonizing activity and NEP enzyme-inhibiting activity. Inone aspect of these methods, the compound is a compound of formula I ora pharmaceutically acceptable salt thereof. Still another aspect of theinvention pertains to a method for antagonizing an AT₁ receptor in amammal comprising administering to the mammal, an AT₁receptor-antagonizing amount of a compound of the invention. Yet anotheraspect of the invention pertains to a method for inhibiting a NEP enzymein a mammal comprising administering to the mammal, a NEPenzyme-inhibiting amount of a compound of the invention.

Compounds having both AT₁ receptor-antagonizing activity and NEPenzyme-inhibiting activity, as well as the compounds of formula I andpharmaceutically acceptable salts thereof, that are of particularinterest include those that exhibit an inhibitory constant (pK_(i)) forbinding to an AT₁ receptor greater than or equal to about 5.0; inparticular those having a pK_(i) greater than or equal to about 6.0; inone embodiment those having a pK_(i) greater than or equal to about 7.0;more particularly those having a pK_(i) greater than or equal to about8.0; and in yet another embodiment, those having a pK_(i) within therange of about 8.0-10.0. Compounds of particular interest also includethose having a NEP enzyme inhibitory concentration (pIC₅₀) greater thanor equal to about 5.0; in one embodiment those having a pIC₅₀ greaterthan or equal to about 6.0; in particular those having a pIC₅₀ greaterthan or equal to about 7.0; and most particularly those having a pIC₅₀within the range of about 7.0-10.0. Compounds of further interestinclude those having a pK_(i) for binding to an AT₁ receptor greaterthan or equal to about 7.5 and having a NEP enzyme pIC₅₀ greater than orequal to about 7.0.

Since compounds of the invention possess AT₁ receptor antagonistactivity and NEP inhibition activity, such compounds are also useful asresearch tools. Accordingly, one aspect of the invention pertains to amethod of using a compound of the invention as a research tool, themethod comprising conducting a biological assay using a compound of theinvention. Compounds of the invention can also be used to evaluate newchemical compounds. Thus another aspect of the invention relates to amethod of evaluating a test compound in a biological assay, comprising:(a) conducting a biological assay with a test compound to provide afirst assay value; (b) conducting the biological assay with a compoundof the invention to provide a second assay value; wherein step (a) isconducted either before, after or concurrently with step (b); and (c)comparing the first assay value from step (a) with the second assayvalue from step (b). Exemplary biological assays include an AT₁ receptorbinding assay and a NEP enzyme inhibition assay. Still another aspect ofthe invention is directed to a method of studying a biological system orsample comprising an AT₁ receptor, a NEP enzyme, or both, the methodcomprising: (a) contacting the biological system or sample with acompound of the invention; and (b) determining the effects caused by thecompound on the biological system or sample.

The invention is also directed to processes and intermediates useful forpreparing compounds of the invention. Accordingly, another aspect of theinvention relates to a process of preparing compounds of the invention.Another aspect of the invention relates to a process of preparing apharmaceutically acceptable salt of a compound of formula I, comprisingcontacting a compound of formula I in free acid or base form with apharmaceutically acceptable base or acid. In other aspects, theinvention is directed to products prepared by any of the processesdescribed herein, as well as novel intermediates used in such process.In one aspect of the invention, these novel intermediates have formulaII, III or IV.

Yet another aspect of the invention is directed to the use of a compoundhaving both AT₁ receptor-antagonizing activity and NEP enzyme-inhibitingactivity for the manufacture of a medicament, especially for themanufacture of a medicament useful for treating hypertension or acutedecompensated heart failure. In one aspect of these uses, the compoundis a compound of formula I or a pharmaceutically acceptable saltthereof. Another aspect of the invention is directed to use of acompound of the invention for antagonizing an AT₁ receptor or forinhibiting a NEP enzyme in a mammal. Still another aspect of theinvention pertains to the use of a compound of the invention as aresearch tool. Other aspects and embodiments of the invention aredisclosed herein.

DETAILED DESCRIPTION OF THE INVENTION

The invention is directed to compounds of formula I:

and pharmaceutically acceptable salts thereof.

As used herein, the term “compound of the invention” is intended toinclude compounds of formula I as well as the species embodied informulas Ia, Ib, Ic, Id, and Ie. In addition, the compounds of theinvention may also contain several basic or acidic groups (for example,amino or carboxyl groups) and therefore, such compounds can exist as afree base, free acid, or in various salt forms. All such salt forms areincluded within the scope of the invention. Furthermore, solvates ofcompounds of formula I or salts thereof are included within the scope ofthe invention. Finally, the compounds of the invention may also exist asprodrugs. Accordingly, those skilled in the art will recognize thatreference to a compound herein, for example, reference to a “compound ofthe invention” includes reference to a compound of formula I as well asto pharmaceutically acceptable salts, solvates and prodrugs of thatcompound unless otherwise indicated. Further, the term “or apharmaceutically acceptable salt, solvate and/or prodrug thereof” isintended to include all permutations of salts and solvates, such as asolvate of a pharmaceutically acceptable salt.

The compounds of formula I may contain one or more chiral centers and somay exist in a number of stereoisomeric forms. When such chiral centersare present, the invention is directed to racemic mixtures, purestereoisomers (enantiomers or diastereomers), stereoisomer-enrichedmixtures, and the like unless otherwise indicated. When a chemicalstructure is depicted without any stereochemistry, it is understood thatall possible stereoisomers are encompassed by such structure. Thus, forexample, the term “compound of formula I” is intended to include allpossible stereoisomers of the compound. Similarly, when a particularstereoisomer is shown or named herein, it will be understood by thoseskilled in the art that minor amounts of other stereoisomers may bepresent in the compositions of the invention unless otherwise indicated,provided that the utility of the composition as a whole is noteliminated by the presence of such other isomers. Individual enantiomersmay be obtained by numerous methods that are well known in the art,including chiral chromatography using a suitable chiral stationary phaseor support, or by chemically converting them into diastereomers,separating the diastereomers by conventional means such aschromatography or recrystallization, then regenerating the originalenantiomers. Additionally, where applicable, all cis-trans or E/Zisomers (geometric isomers), tautomeric forms and topoisomeric forms ofthe compounds of the invention are included within the scope of theinvention unless otherwise specified.

Compounds of formula I may contain one or more chiral centers. Onepossible chiral center could be present in the X portion of thecompound. For example, a chiral center exists at a carbon atom in thealkylene moiety in X that is substituted with an R^(4b) group such as—C₁₋₆alkyl, for example —CH₃. This chiral center is present at thecarbon atom indicated by the symbol * in the following partial formula:

Another possible chiral center could be present in the —CR⁵R⁶R⁷ portionof the compound, when R⁶ is a group such as —C₁₋₆alkyl, for example—CH₂CH(CH₃)₂, and R⁷ is H. This chiral center is present at the carbonatom indicated by the symbol ** in the following formula:

In one embodiment of the invention, the carbon atom identified by thesymbol * and/or** has the (R) configuration. In this embodiment,compounds of formula I have the (R) configuration at the carbon atomidentified by the symbol * and/or ** or are enriched in a stereoisomericform having the (R) configuration at this carbon atom (or atoms). Inanother embodiment, the carbon atom identified by the symbol * and/or **has the (S) configuration. In this embodiment, compounds of formula Ihave the (S) configuration at the carbon atom identified by the symbol *and/or ** or are enriched in a stereoisomeric form having the (S)configuration at this carbon atom. It is understood that a compound mayhave a chiral center at both the * and the ** carbon atoms. In suchcases, four possible diastereomers can exist. In some cases, in order tooptimize the therapeutic activity of the compounds of the invention, forexample, as hypertensive agents, it may be desirable that the carbonatom identified by the symbol * and/or ** have a particular (R) or (S)configuration.

The compounds of the invention, as well as those compounds used in theirsynthesis, may also include isotopically-labeled compounds, that is,where one or more atoms have been enriched with atoms having an atomicmass different from the atomic mass predominately found in nature.Examples of isotopes that may be incorporated into the compounds offormula I, for example, include, but are not limited to, ²H, ³H, ¹³C,¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, ³⁵S, ³⁶Cl, and ¹⁸F.

The compounds of formula I have been found to possess AT₁ receptorantagonizing activity and NEP enzyme inhibition activity. Among otherproperties, such compounds are expected to be useful as therapeuticagents for treating diseases such as hypertension. By combining dualactivity into a single compound, double therapy can be achieved; bothAT₁ receptor antagonist activity and NEP enzyme inhibition activity canbe obtained using a single active component. Since pharmaceuticalcompositions containing one active component are typically easier toformulate than compositions containing two active components, suchsingle-component compositions provide a significant advantage overcompositions containing two active components. In addition, certaincompounds of the invention have also been found to be selective forinhibition of the AT₁ receptor over the angiotensin II type 2 (AT₂)receptor, a property that may have therapeutic advantages.

The nomenclature used herein to name the compounds of the invention isillustrated in the Examples herein. This nomenclature has been derivedusing the commercially-available AutoNom software (MDL, San Leandro,Calif.).

REPRESENTATIVE EMBODIMENTS

The following substituents and values are intended to providerepresentative examples of various aspects and embodiments of theinvention. These representative values are intended to further defineand illustrate such aspects and embodiments and are not intended toexclude other embodiments or to limit the scope of the invention. Inthis regard, the representation that a particular value or substituentis preferred is not intended in any way to exclude other values orsubstituents from the invention unless specifically indicated.

The values for r are 0, 1 or 2. In one embodiment, r is 1. Each —CH₂—group in the —(CH₂)_(r)— group may be substituted with 1 or 2substituents independently selected from —C₁₋₄alkyl (for example, —CH₃),and fluoro. In one particular embodiment, the —(CH₂)_(r)— group isunsubstituted; in another embodiment, one or two —CH₂— groups in—(CH₂)_(r)— are substituted with a —C₁₋₄alkyl group.

Ar represents an aryl group selected from:

Each ring in the Ar moiety may be substituted with 1 to 3 substituentsindependently selected from —OH, —C₁₋₆alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl,—CN, halo, —O—C₁₋₆alkyl, —S—C₁₋₆alkyl, —S(O)—C₁₋₆alkyl,—S(O)₂—C₁₋₄alkyl, -phenyl, —NO₂, —NH₂, —NH—C₁₋₆alkyl and —N(C₁₋₆alkyl)₂.Furthermore, each of the aforementioned alkyl, alkenyl and alkynylgroups are optionally substituted with 1 to 5 fluoro atoms.

In one particular embodiment, each ring in the Ar moiety may besubstituted with 1 to 2 substituents independently selected from —OH,—C₁₋₄alkyl (for example, —CH₃), halo (for example bromo, fluoro, chloro,and di-fluoro), —O—C₁₋₄alkyl (for example, —OCH₃), and -phenyl.Exemplary substituted Ar moieties include:

Of particular interest is where Ar is substituted with 1 or 2 haloatoms.

It is understood that:

represents:

In one particular embodiment, Ar is an aryl group selected from:

R¹ is selected from —COOR^(1a), —NHSO₂R^(1b), —SO₂NHR^(1d), —SO₂OH,—C(O)NH—SO₂R^(1c), —P(O)(OH)₂, —CN, —O—CH(R^(1e))—COOH, tetrazol-5-yl,

The R^(1a) moiety is H, —C₁₋₆alkyl, —C₁₋₃alkylenearyl,—C₁₋₃alkyleneheteroaryl, —C₃₋₇cycloalkyl, —CH(C₁₋₄alkyl)OC(O)R^(1aa),—C₀₋₆alkylenemorpholine,

R^(1aa) is —O—C₁₋₆alkyl, —O—C₃₋₇cycloalkyl, —NR^(1ab)R^(1ac), or—CH(NH₂)CH₂COOCH₃. R^(1ab) and R^(1ac) are independently selected fromH, —C₁₋₆alkyl, and benzyl, or are taken together as —(CH₂)₃₋₆—.

The R^(1b) moiety is R^(1c) or —NHC(O)R^(1c). The R^(1c) group is—C₁₋₆alkyl, —C₀₋₆alkylene-O—R^(1ca), —C₁₋₅alkylene-NR^(1cb)R^(1cc), or—C₀₋₄alkylenearyl. The R^(1ca) moiety is H, —C₁₋₆alkyl, or—C₁₋₆alkylene-O—C₁₋₆alkyl. The R^(1cb) and R^(1cc) groups areindependently selected from H and —C₁₋₆alkyl, or are taken together as—(CH₂)₂—O—(CH₂)₂— or —(CH₂)₂—N[C(O)CH₃]—(CH₂)₂—. The R^(1d) moiety is H,R^(1c), —C(O)R^(1c), or —C(O)NHR^(1c). The R^(1e) group is C₁₋₄alkyl oraryl.

Each alkyl and each aryl in R¹ is optionally substituted with 1 to 7fluoro atoms. In addition, the term “alkyl” is intended to includedivalent alkylene groups such as those present in —C₁₋₃alkylenearyl and—C₁₋₃alkyleneheteroaryl, for example. Further, each aryl group thatmight be present in R¹, may be substituted with 1 to 3 —OH, —C₁₋₆alkyl,—C₂₋₄alkenyl, —C₂₋₄alkynyl, —CN, halo, —O—C₁₋₆alkyl, —S—C₁₋₆alkyl,—S(O)—C₁₋₆alkyl, —S(O)₂—C₁₋₄alkyl, -phenyl, —NO₂, —NH₂, —NH—C₁₋₆alkyl,or —N(C₁₋₆alkyl)₂ groups. Further, each of the aforementioned alkyl,alkenyl and alkynyl groups may be substituted with 1 to 5 fluoro atoms.It is understood that when referring to “each alkyl” and “each aryl”group in R¹, the terms also include any alkyl and aryl groups that mightbe present in the R^(1a) through R^(1e) moieties.

In one embodiment, R¹ is —COOR^(1a) and R^(1a) is H. In anotherembodiment, R¹ is —COOR^(1a) and R^(1a) is —C₁₋₆alkyl, examples of whichinclude —CH₃, —CH₂CH₃, —(CH₂)₂CH₃, —(CH₂)₂—CF₃, —CH₂CH(CH₃)₂, —CH(CH₃)₂,—CH(CH₃)—CF₃, —CH(CH₂F)₂, —C(CH₃)₃, —(CH₂)₃CH₃, and —(CH₂)₂—CF₂CF₃.Thus, examples of R¹ include —C(O)OCH₃, —COOCH₂CH₃, and so forth.

In one embodiment, R¹ is —COOR^(1a) and R^(1a) is —C₁₋₃alkylenearyl, forexample, a benzyl group, which may be substituted such as chlorobenzyl,fluorobenzyl, difluorobenzyl, -benzyl-CH₃, -benzyl-CF₃, and-benzyl-O—CF₃. Thus, examples of R¹ include: —C(O)OCH₂-benzyl,

In one embodiment, R¹ is —COOR^(1a) and R^(1a) is—C₁₋₃alkyleneheteroaryl, examples of which include —CH₂-pyridinyl. Inone embodiment, R¹ is —COOR^(1a) and R^(1a) is —C₃₋₇cycloalkyl, examplesof which include cyclopentyl.

In yet another embodiment R¹ is —COOR^(1a) and R^(1a) is—CH(C₁₋₄alkyl)OC(O)R^(1aa), where R^(1aa) is —O—C₁₋₆alkyl,—O—C₃₋₇cycloalkyl, —NR^(1ab)R^(1ac), or —CH(NH₂)CH₂COOCH₃. R^(1ab) andR^(1ac) are independently selected from H, —C₁₋₆alkyl, and benzyl, orare taken together as —(CH₂)₃₋₆—. Examples of —O—C₁₋₆alkyl groupsinclude —O—CH₂CH₃ and —O—CH(CH₃)₂. Exemplary —O—C₃₋₇cycloalkyl groupsinclude —O-cyclohexyl. Thus, examples of R¹ include—C(O)OCH(CH₃)OC(O)—O—CH₂CH₃, —C(O)OCH(CH₃)OC(O)—O—CH(CH₃)₂, and—C(O)OCH(CH₃)OC(O)—O-cyclohexyl.

In one embodiment, R¹ is —COOR^(1a) and R^(1a) is—C₀₋₆alkylenemorpholine, examples of which include —(CH₂)₂-morpholineand —(CH₂)₃-morpholine. In another embodiment, R^(1a) is

In one embodiment, R¹ is —NHSO₂R^(1b) and R^(1b) is R^(1c). The R^(1c)group is —C₁₋₆alkyl, —C₀₋₆alkylene-O—R^(1ca),—C₁₋₅alkylene-NR^(1cb)R^(1cc), or —C₀₋₄alkylenearyl. The R^(1ca) moietyis H, —C₁₋₆alkyl, or —C₁₋₆alkylene-O—C₁₋₆alkyl. The R^(1cb) and R^(1cc)groups are independently selected from H and —C₁₋₆alkyl, or are takentogether as —(CH₂)₂—O—(CH₂)₂— or —(CH₂)₂—N[C(O)CH₃]—(CH₂)₂—. In oneembodiment, R^(1c) is —C₁₋₆alkyl, such that exemplary R¹ groups include—NHSO₂—CH₃ and the fluoro-substituted group, —NHSO₂—CF₃. In anotherembodiment, R^(1c) is —C₀₋₄alkylenearyl, such that exemplary R¹ groupsinclude —NHSO₂-phenyl.

In another embodiment, R¹ is —NHSO₂R^(1b) and R^(1b) is —NHC(O)R^(1c),where R^(1c) is defined above. In a particular embodiment, R¹ is—NHSO₂R^(1b), R^(1b) is —NHC(O)R^(1c), and R^(1c) is —C₁₋₆alkyl or—C₀₋₄alkylenearyl.

In one embodiment, R¹ is —SO₂NHR^(1d) and R^(1d) is H. In anotherembodiment, R¹ is —SO₂NHR^(1d) and R^(1d) is R^(1c), where R^(1c) isdefined above. In a particular embodiment, R^(1c) is —C₁₋₆alkyl or—C₀₋₄alkylenearyl. When R^(1c) is —C₁₋₆alkyl, exemplary R¹ groupsinclude the fluoro-substituted groups —SO₂NH—CF₃, —SO₂NH—CHF₂,—SO₂NH—CF₂CH₂F and —SO₂NH—CF₂CF₂CF₃.

In another embodiment, R¹ is —SO₂NHR^(1d) and R^(1d) is —C(O)R^(1c),where R^(1c) is defined above. In one embodiment of particular interest,R^(1c) is —C₁₋₆alkyl or —C₀₋₄alkylenearyl. When R^(1c) is —C₁₋₆alkyl,exemplary R¹ groups include —SO₂NHC(O)CH₃ and —SO₂NHC(O)(CH₂)₂CH₃. WhenR^(1c) is —C₀₋₆alkylene-O—R^(1ca) and R^(1ca) is H, exemplary R¹ groupsinclude —SO₂NHC(O)CH₂OH, —SO₂NHC(O)CH(CH₃)OH, and —SO₂NHC(O)C(CH₃)₂OH.When R^(1c) is —C₀₋₆alkylene-O—R^(1ca) and R^(1ca) is —C₁₋₆alkyl,exemplary R¹ groups include —SO₂NHC(O)CH₂—O—CH₃ and —SO₂NHC(O)—O—CH₂CH₃.When R^(1c) is —C₀₋₆alkylene-O—R^(1ca) and R^(1ca) is—C₁₋₆alkylene-O—C₁₋₆alkyl, exemplary R¹ groups include—SO₂NHC(O)CH₂—O—(CH₂)₂—O—CH₃. When R^(1c) is—C₁₋₅alkylene-NR^(1cb)R^(1cc), exemplary R¹ groups include—SO₂NHC(O)CH₂N(CH₃)₂, —SO₂NHC(O)—CH₂—NH₂, and —SO₂NHC(O)—CH(CH₃)—NH₂.Another example when R^(1c) is —C₁₋₅alkylene-NR^(1cb)R^(1cc) is wherethe R^(1cb) and R^(1cc) are taken together as —(CH₂)₂—O—(CH₂)₂— or—(CH₂)₂—N[C(O)CH₃]—(CH₂)₂—. Such exemplary R¹ groups include:

In another embodiment, R¹ is —SO₂NHR^(1d) and R^(1d) is —C(O)NHR^(1c),where R^(1c) is defined above. In a particular embodiment, R^(1c) is—C₁₋₆alkyl or —C₀₋₄alkylenearyl. When R^(1c) is —C₁₋₆alkyl, exemplary R¹groups include —SO₂NHC(O)NH—CH₂CH₃ and —SO₂NHC(O)NH—(CH₂)₂CH₃. WhenR^(1c) is —C₀₋₄alkylenearyl, exemplary R¹ groups include—SO₂NHC(O)NH-phenyl.

In another embodiment, R¹ is —SO₂OH, and in still another embodiment, R¹is —P(O)(OH)₂. In yet another embodiment, R¹ is —CN.

In another embodiment, R¹ is —C(O)NH—SO₂R^(1c), where R^(1c) is definedabove. In a particular embodiment, R^(1c) is —C₁₋₆alkyl or—C₀₋₄alkylenearyl. When R^(1c) is —C₁₋₆alkyl, exemplary R¹ groupsinclude —C(O)—NH—SO₂—CH₃, —C(O)—NH—SO₂—CH₂CH₃ and the fluoro-substituted—C(O)—NH—SO₂—CF₃ group.

In another embodiment, R¹ is —O—CH(R^(1e))—COOH, where R^(1e) is—C₁₋₄alkyl or aryl. Examples of such R¹ groups include, —O—CH(CH₃)—COOHand —O—CH(phenyl)-COOH.

In an embodiment of particular interest, R¹ is tetrazol-5-yl. In anotherembodiment, R¹ is:

In one particular embodiment, R¹ is —COOR^(1a), where R^(1a) is—C₁₋₆alkyl, —C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl, —C₃₋₇cycloalkyl,—CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,

In one aspect of the invention, these compounds may find particularutility as prodrugs or as intermediates in the synthetic proceduresdescribed herein. In one particular embodiment, R¹ is —COOR^(1a) andR^(1a) is —C₁₋₆alkyl.

In another particular embodiment, R¹ is selected from —COOR^(1a) whereR^(1a) is H, —NHSO₂R^(1b), —SO₂NHR^(1d), —SO₂OH, —C(O)NH—SO₂R^(1c),—P(O)(OH)₂, —CN, —O—CH(R^(1e))—COOH, tetrazol-5-yl,

In one particular embodiment, R¹ is selected from —COOR^(1a),—SO₂NHR^(1d), and tetrazol-5-yl. In another embodiment, R¹ is selectedfrom —COOH, —SO₂NHC(O)—C₁₋₆alkyl, and tetrazol-5-yl.

R³ is selected from —C₁₋₁₀alkyl, —C₂₋₁₀alkenyl, —C₃₋₁₀alkynyl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, —C₂₋₃alkenylene-C₃₋₇cycloalkyl,—C₂₋₃alkynylene-C₃₋₇cycloalkyl,—C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b),—C₀₋₅alkylene-O—C₀₋₅alkylene-R^(3b),—C₁₋₅alkylene-S—C₁₋₅alkylene-R^(3b), and —C₀₋₃alkylenearyl. The R^(3a)moiety is H, —C₁₋₆alkyl, —C₃₋₇cycloalkyl, or —C₀₋₃alkylenearyl (forexample, —C₀₋₁alkylenearyl such as phenyl and benzyl). R^(3b) isselected from H, —C₁₋₆alkyl, —C₃₋₇cycloalkyl, —C₂₋₄alkenyl,—C₂₋₄alkynyl, and aryl (such as phenyl).

In addition, each alkyl and each aryl in R³ is optionally substitutedwith 1 to 7 fluoro atoms, where the term “alkyl” is intended to includedivalent alkylene groups such as those present in—C₀₋₃alkylene-C₃₋₇cycloalkyl and —C₀₋₃alkylenearyl, for example. Eacharyl in R³, for example in —C₀₋₃alkylenearyl or aryl, may be substitutedwith 1 to 3 —OH, —C₁₋₆alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl, —CN, halo,—O—C₁₋₆alkyl, —S—C₁₋₆alkyl, —S(O)—C₁₋₆alkyl, —S(O)₂—C₁₋₄alkyl, -phenyl,—NO₂, —NH₂, —NH—C₁₋₆alkyl, or —N(C₁₋₆alkyl)₂ groups. Further, each ofthe aforementioned alkyl, alkenyl and alkynyl groups may be substitutedwith 1 to 5 fluoro atoms. It is understood that when referring to “eachalkyl” and “each aryl” group in R³, the terms also include any alkyl andaryl groups that might be present in the R^(3a) and R^(3b) moieties.

In one embodiment, R³ is —C₁₋₁₀alkyl such as —CH₃ or optionallysubstituted with 1 to 7 fluoro atoms such as —CF₃. In anotherembodiment, R³ is —C₂₋₇alkyl such as —CH₂CH₃; and in yet anotherembodiment, R³ is —C₂₋₅alkyl, for example, —(CH₂)₂CH₃, —(CH₂)₃CH₃,—CH₂—CH(CH₃)₂, —CH₂—CH(CH₃)CH₂CH₃, —(CH₂)₂—CH(CH₃)₂, —CH(CH₂CH₃)₂, or—(CH₂)₄CH₃.

In another embodiment, R³ is —C₂₋₁₀alkenyl such as —CH₂CH═CHCH₃. In yetanother embodiment, R³ is —C₃₋₁₀alkynyl such as —CH₂C≡CCH₃.

In another embodiment, R³ is —C₀₋₃alkylene-C₃₋₇cycloalkyl such as-cyclopropyl, —CH₂-cyclopropyl, cyclopentyl, —CH₂-cyclopentyl,—(CH₂)₂-cyclopentyl, and —CH₂-cyclohexyl. In a particular embodiment, R³is —C₀₋₁alkylene-C₃₋₅cycloalkyl. In one embodiment, R³ is—C₂₋₃alkenylene-C₃₋₇cycloalkyl such as —CH₂CH═CH-cyclopentyl; and inanother embodiment, R³ is —C₂₋₃alkynylene-C₃₋₇cycloalkyl such as—CH₂C≡C-cyclopentyl.

In yet another embodiment, R³ is—C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b). In one particular embodiment,R^(3a) is H and R^(3b) is —C₁₋₆alkyl. Examples of such R³ groups include—NHCH₂CH₃, —NHCH(CH₃)₂, —NH(CH₂)₂CH₃, —NH(CH₂)₃CH₃, —NHCH(CH₃)CH₂CH₃,—NH(CH₂)₄CH₃, and —NH(CH₂)₅CH₃.

In one embodiment, R³ is —C₀₋₅alkylene-O—C₀₋₅alkylene-R^(3b). In oneparticular embodiment, R^(3b) is selected from H, —C₁₋₆alkyl and aryl.Examples of such R³ groups include —OCH₃, —OCH₂CH₃, —OCH(CH₃)₂,—O(CH₂)₂CH₃, —O(CH₂)₃CH₃, —OCH₂CH(CH₃)₂, —O-phenyl, and —O-benzyl.

In another embodiment, R³ is —C₁₋₅alkylene-S—C₁₋₅alkylene-R^(3b), and inone particular embodiment R^(3b) is H, such as when R³ is —CH₂—S—CH₂CH₃.In another embodiment, R³ is —C₀₋₃alkylenearyl, such as phenyl, benzyl,and —(CH₂)₂-phenyl.

X is —C₁₋₁₂alkylene-, where at least one —CH₂— moiety in the alkylene isreplaced with a —NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety. Thus X can be—C₁alkylene-, —C₁alkylene-, —C₂alkylene-, —C₃alkylene-, —C₄alkylene-,—C₅alkylene-, —C₆alkylene-, —C₇alkylene-, —C₈alkylene, —C₉alkylene-,—C₁₀alkylene-, —C₁₁alkylene-, and —C₁₂alkylene-, with at least one —CH₂—moiety being replaced. R^(4a) is selected from H, —OH, and —C₁₋₄alkyl.In one embodiment, R^(4a) is H.

Each carbon atom in the —C₁₋₁₂alkylene- group may be substituted withone or more R^(4b) groups. R^(4b) is selected from—C₀₋₅alkylene-COOR^(4c), —C₁₋₆alkyl, —C₀₋₁alkylene-CONH₂,—C₁₋₂alkylene-OH, —C₀₋₃alkylene-C₃₋₇cycloalkyl, 1H-indol-3-yl, benzyl,and hydroxybenzyl, where R^(4c) is H or —C₁₋₄alkyl. In one embodiment,the carbon atoms in —C₁₋₁₂alkylene- are unsubstituted with R^(4b)groups. In another embodiment, 1 or 2 carbon atoms are substituted withone or two R^(4b) groups. In another embodiment, one carbon atom issubstituted with one R^(4b) group. In one particular embodiment, R^(4b)is —COOH, benzyl, or —C₁₋₆alkyl, including —C₁₋₃alkyl groups such as—CH₃ and —CH(CH₃)₂.

In addition, one —CH₂— moiety in X may be replaced with a group selectedfrom —C₄₋₈cycloalkylene-, —CR^(4d)═CH—, and —CH═CR^(4d)—. R^(4d) isselected from —CH₂-thiophene and phenyl. In one embodiment, none of the—CH₂— moieties are so replaced. In another embodiment, one —CH₂— moietyis replaced with —C₄₋₈cycloalkylene-, for example, cyclohexylene. Inanother embodiment, one —CH₂— moiety is replaced with —CH═CR^(4d)—,where R^(4d) is —CH₂-thiophene such as —CH₂-thiophen-2-yl.

Each alkyl and each aryl in R^(4a), R^(4b), R^(4c), and R^(4d), may besubstituted with 1 to 7 fluoro atoms, and the term “alkyl” is intendedto include divalent alkylene groups such as that present in—C₀₋₅alkylene-COOR^(4c), for example. It is noted that the R^(4b) group,—C₀₋₃alkylene-C₃₋₇cycloalkyl, is intended to include a C₃₋₇cycloalkyllinked to the X —C₁₋₁₂alkylene- chain by a bond as well as aC₃₋₇cycloalkyl that is directly attached to the chain, as illustratedbelow:

In one embodiment, one to four —CH₂— moieties are replaced with—NR^(4a)—C(O)— or —C(O)—NR^(4a)— moieties, in another embodiment one—CH₂— moiety is replaced, one example of which includes —(CH₂)₂—NHC(O)—.In one embodiment, X is —C₂₋₁₁alkylene- and 1, 2, or 3 —CH₂— moietiesare replaced with a —NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety. In anotherembodiment, X is —C₂₋₅alkylene-, where 1 or 2 —CH₂— moieties arereplaced. When more than one —CH₂— moiety in —C₁₋₁₂alkylene- is replacedwith a NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety, the replaced moieties maybe contiguous or non-contiguous. In one particular embodiment, thereplaced moieties are contiguous. Exemplary X groups include thefollowing, which depict: examples where one or more —CH₂— moieties arereplaced with —NR^(4a)—C(O)— or —C(O)—NR^(4a)— moieties; examples where—CH₂— moieties are replaced with a group selected from—C₄₋₈cycloalkylene-, —CR^(4d)═CH—, and —CH═CR^(4d)—; and examples wherecarbon atoms in the —C₁₋₁₂alkylene- group are substituted with one ormore R^(4b) groups:

—C₁alkylene- with one —CH₂— moiety replaced:

-   -   —C(O)NH—    -   —NHC(O)—

C₂alkylene- with one —CH₂— moiety replaced:

-   -   —CH₂—NHC(O)—    -   —C(O)NH—CH₂—    -   —CH₂—C(O)NH—    -   —CH[CH(CH₃)₂]—C(O)NH—    -   —CH(COOH)—NHC(O)—

—C₂alkylene- with two —CH₂— moieties replaced:

-   -   C(O)NH—NHC(O)—    -   —CH═C(—CH₂-thiopheny-2-yl)-C(O)NH—

—C₃alkylene- with one —CH₂— moiety replaced:

-   -   —(CH₂)₂—NHC(O)—    -   —(CH₂)₂—C(O)NH—    -   —CH(CH₃)—CH₂—NHC(O)—    -   —CH[CH(CH₃)₂]—CH₂—NHC(O)—    -   —CH(COOH)—CH₂—NHC(O)—    -   —CH₂—CH(COOH)—NHC(O)—    -   —CH₂—C(CH₃)₂—NHC(O)—

—C₃alkylene- with two —CH₂— moieties replaced:

-   -   —NHC(O)—CH₂—NHC(O)—

—C₄alkylene- with one —CH₂— moiety replaced:

-   -   —(CH₂)₃—NHC(O)—    -   —C(O)NH—CH₂—CH(COOH)—CH₂—

—C₄alkylene- with two —CH₂— moieties replaced:

-   -   —C(O)NH—CH(benzyl)-CH₂—NHC(O)—    -   —C(O)NH—CH(benzyl)-CH₂—C(O)NH—    -   —CH₂—NHC(O)—CH₂—NHC(O)—

—C₄alkylene- with three —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)-cyclohexylene-NHC(O)—    -   —CH₂—N(OH)C(O)-cyclohexylene-NHC(O)—

—C₅alkylene- with two —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)—CH₂—CH(COOH)—NHC(O)—    -   —CH₂—NHC(O)—(CH₂)₂—NHC(O)—    -   —C(O)NH—(CH₂)₂—C(O)N(OH)—CH₂—    -   —C(O)NH—(CH₂)₂—CH(COOH)—NHC(O)—    -   —CH(COOH)—CH₂—NHC(O)—CH₂—NHC(O)—    -   —(CH₂)₂—NHC(O)-cyclohexylene-NHC(O)—    -   —CH₂—CH(COOH)—NHC(O)—CH₂—NHC(O)—

—C₆alkylene- with two —CH₂— moieties replaced:

-   -   —C(O)NH—(CH₂)₄—NHC(O)—    -   —CH₂—NHC(O)—(CH₂)₂—CH(COOH)—NHC(O)—    -   —C(O)NH—(CH₂)₃—CH(COOH)—NHC(O)—

—C₆alkylene- with three —CH₂— moieties replaced:

-   -   —C(O)NH—(CH₂)₂—NHC(O)—CH₂—NHC(O)—

—C₆alkylene- with four —CH₂— moieties replaced:

-   -   —C(O)NH—(CH₂)₂—NHC(O)-cyclohexylene-NHC(O)—

—C₇alkylene- with two —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)—(CH₂)₄—NHC(O)—    -   —C(O)NH—(CH₂)₄—CH(COOH)—NHC(O)—

—C₇alkylene- with three —CH₂— moieties replaced:

-   -   —CH[CH(CH₃)₂]—C(O)NH—(CH₂)₂—NHC(O)—CH₂—NHC(O)—

—C₇alkylene- with four —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)—(CH₂)₂—NHC(O)-cyclohexylene-NHC(O)—    -   —CH₂—C(O)NH—(CH₂)₂—NHC(O)-cyclohexylene-NHC(O)—

—C₈alkylene- with three —CH₂— moieties replaced:

-   -   —C(O)NH—(CH₂)₄—NHC(O)—CH₂—NHC(O)—

—C₈alkylene- with four —CH₂— moieties replaced:

-   -   —C(O)NH—(CH₂)₄—NHC(O)-cyclohexylene-NHC(O)—

—C₉alkylene- with two —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)—(CH₂)₆—NHC(O)—

C₉alkylene- with four —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)—(CH₂)₄—NHC(O)-cyclohexylene-NHC(O)—

C₁₀alkylene- with four —CH₂— moieties replaced:

-   -   —C(O)NH—(CH₂)₆—NHC(O)-cyclohexylene-NHC(O)—

—C₁₁alkylene- with three —CH₂— moieties replaced:

-   -   —CH[CH(CH₃)₂]—C(O)NH—(CH₂)₆—NHC(O)—CH₂—NHC(O)—

C₁₁alkylene- with four —CH₂— moieties replaced:

-   -   —CH₂—NHC(O)—(CH₂)₆—NHC(O)-cyclohexylene-NHC(O)—        In one particular embodiment, X is —(CH₂)₂—NHC(O)— or        —(CH₂)₂—C(O)NH—.

R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)N^(5b)R^(5c), —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d),—NH—C₀₋₁alkylene-P(O)(OR^(5e))₂, —C₀₋₃alkylene-P(O)OR^(5e)R^(5f),—C₀₋₂alkylene-CHR^(5g)—COOH and —C₀₋₃alkylene-C(O)NR^(5h)—CHR^(5i)—COOH.Each alkyl and each aryl in R⁵ is optionally substituted with 1 to 7fluoro atoms, where the term “alkyl” is intended to include divalentalkylene groups such as those present in —C₀₋₃alkylene-SR^(5a) and—C₀₋₃alkylene-P(O)OR^(5e)R^(5f), for example. Each aryl in R⁵ may besubstituted with 1 to 3 —OH, —C₁₋₆alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl,—CN, halo, —O—C₁₋₆alkyl, —S—C₁₋₆alkyl, —S(O)—C₁₋₆alkyl,—S(O)₂—C₁₋₄alkyl, -phenyl, —NO₂, —NH₂, —NH—C₁₋₆alkyl, or —N(C₁₋₆alkyl)₂groups. Further, each of the aforementioned alkyl, alkenyl and alkynylgroups may be substituted with 1 to 5 fluoro atoms. It is understoodthat when referring to “each alkyl” and “each aryl” group in R⁵, theterms also include any alkyl and aryl groups that might be present inthe R^(5a-5i), R^(5aa), R^(5ab), R^(5ba), R^(5bb), R^(5bc), R^(5ca),R^(5da), R^(5db), R^(5ea), R^(5eb), R^(5ec), R^(5fa), and R^(5fb)moieties.

In one embodiment, R⁵ is —C₀₋₃alkylene-SR^(5a). R^(5a) is H or—C(O)—R^(5aa). The R^(5aa) group is —C₁₋₆alkyl,—C₀₋₆alkylene-C₃₋₇cycloalkyl, —CO-alkylenearyl, —C₀₋₆alkyleneheteroaryl,—C₀₋₆alkylenemorpholine, —C₀₋₆alkylenepiperazine-CH₃, —CH(NH₂)-aa whereaa is an amino acid side chain, -2-pyrrolidine, —C₀₋₆alkylene-OR^(5ab),—O—C₀₋₆alkylenearyl, —C₁₋₂alkylene-OC(O)—C₁₋₆alkyl,—C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, or—O—C₁₋₂alkylene-OC(O)O—C₁₋₆alkyl. The R^(5ab) group is H or —C₁₋₆alkyl.In one specific embodiment, R^(5a) is H, for example, R⁵ may be —SH or—CH₂SH. In another embodiment, R^(5a) is —C(O)—R^(5aa), where R^(5aa) is—C₁₋₆alkyl. Exemplary —C₁₋₆alkyl groups include —CH₃, —CH₂CH₃,—CH(CH₃)₂, —C(CH₃)₃, and —CH₂CH(CH₃)₂. Thus, examples of R⁵ include—SC(O)CH₃, —CH₂SC(O)CH₃, —CH₂SC(O)CH₂CH₃, —CH₂SC(O)CH(CH₃)₂ and—CH₂SC(O)C(CH₃)₃, and —CH₂SC(O)CH₂CH(CH₃)₂. In one embodiment, R^(5a) isselected from H and —C(O)—C₁₋₆alkyl.

In one embodiment, R^(5a) is —C(O)—R^(5aa), where R^(5aa) is—C₀₋₆alkylene —C₃₋₇cycloalkyl. Exemplary C₃₋₇cycloalkyl groups includecyclopentyl and cyclohexyl. Thus, examples of R⁵ include—CH₂SC(O)-cyclopentyl, —CH₂SC(O)-cyclohexyl, and—CH₂SC(O)—CH₂-cyclopentyl. In another embodiment, R^(5a) is—C(O)—R^(5aa), where R^(5aa) is —C₀₋₆alkylenearyl. In one specificembodiment, the aryl is optionally substituted with 1 to 3 substituentssuch as —O—C₁₋₆alkyl. Exemplary aryl groups include phenyl and-phenyl-OCH₃. Thus, examples of R⁵ include —CH₂SC(O)-phenyl and—CH₂SC(O)-phenyl-OCH₃. In yet another embodiment, R^(5a) is—C(O)—R^(5aa), where R^(5aa) is —C₀₋₆alkyleneheteroaryl. Exemplaryheteroaryl groups include furanyl, thienyl and pyridinyl. Thus, examplesof R⁵ include: —CH₂SC(O)-2-pyridine, —CH₂SC(O)-3-pyridine, and—CH₂SC(O)-4-pyridine. In another embodiment, R^(5a) is —C(O)—R^(5a),where R^(5aa) is —C₀₋₆alkylenemorpholine:

more particularly, —C₁₋₃alkylenemorpholine. Thus, examples of R⁵ include—CH₂S—C(O)CH₂-morpholine and —CH₂S—C(O)(CH₂)₂-morpholine. In anotherembodiment, R^(5a) is —C(O)—R^(5aa), where R^(5aa) is—C₀₋₆alkylenepiperazine-CH₃. Thus, examples of R⁵ include—CH₂S—C(O)(CH₂)₂-piperazine-CH₃. In one embodiment, R^(5a) is—C(O)—R^(5aa), where R^(5aa) is —CH(N—H₂)-aa where aa is an amino acidside chain. For example, the amino acid side chain could be —CH(CH₃)₂,the valine side chain. Thus, one example of R⁵ is—CH₂S—C(O)CH(NH₂)—CH(CH₃)₂. In yet another embodiment, R^(5a) is—C(O)—R^(5aa), where R^(5aa) is -2-pyrrolidine:

Thus, an example of R⁵ is —CH₂S—C(O)-2-pyrrolidine.

In another embodiment, R^(5a) is —C(O)—R^(5aa), where R^(5aa) is—C₀₋₆alkylene-OR^(5ab). In one embodiment, R^(5ab) is H, such thatR^(5a) is —C(O)—C₀₋₆alkylene-OH. In another embodiment, R^(5ab) is—C₁₋₆alkyl, such that R^(5a) is —C(O)—C₀₋₆alkylene-O—C₁₋₆alkyl, forexample, R⁵ may be —CH₂SC(O)—O—CH₂CH₃.

In another embodiment, R^(5a) is —C(O)—R^(5aa), where R^(5aa) is—O—C₀₋₆alkylenearyl. In yet another embodiment, R^(5a) is —C(O)—R^(5aa),where R^(5aa) is —C₁₋₂alkylene-OC(O)—C₁₋₆alkyl and in anotherembodiment, R^(5a) is —C(O)—R^(5aa), where R^(5aa) is—C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl. In yet another embodiment, R^(5a)is —C(O)—R^(5aa), where R^(5aa) is —O—C₁₋₂alkylene-OC(O)O—C₁₋₆alkyl, forexample, R⁵ may be —CH₂SC(O)OCH(CH₃)—OC(O)O—CH(CH₃)₂.

In one embodiment, R⁵ is —C₀₋₃alkylene-C(O)NR^(5b)R^(5c). The R^(5b)moiety is H, —OH, —OC(O)R^(5ba), —CH₂COOH, —O-benzyl, -pyridyl, or—OC(S)NR^(5bb)R^(5bc). R^(5ba) is —C₁₋₆alkyl, —O—CH₂-aryl (for example,—OCH₂-phenyl), —CH₂—O-aryl (for example, —CH₂O-phenyl), or—NR^(5bb)R^(5bc). The R^(5bb) and R^(5bc) moieties are independentlyselected from H and —C₁₋₄alkyl. In one embodiment, R^(5b) is —OH or—OC(O)R^(5ba), where —R^(5ba) is —C₁₋₆alkyl. R^(5c) is H, —C₁₋₆alkyl, or—C(O)—R^(5ca). R^(5ca) is —C₁₋₆alkyl, —C₃₋₇cycloalkyl, aryl, orheteroaryl. In one particular embodiment, R^(5c) is H. In anotherembodiment, R^(5b) is —OH and R^(5c) is H, for example, R⁵ may be—C(O)NH(OH) or —CH₂C(O)NH(OH). In another embodiment, R^(5b) is—OC(O)R^(5ba), where —R^(5ba) is —C₁₋₆alkyl, and R^(5c) is H, forexample, R⁵ may be —C(O)N[OC(O)CH₃]H or —C(O)N[OC(O)C(CH₃)₃]H. In stillanother embodiment, both R^(5b) and R^(5c) are H, for example, R⁵ may be—C(O)NH₂. In another embodiment, R^(5b) is —CH₂COOH and R^(5c) is H, forexample, R⁵ may be —C(O)N(CH₂COOH)H. In yet another embodiment, R^(5b)is —OC(O)R^(5ba), where —R^(5ba) is —O—CH₂-aryl or —CH₂—O-aryl, forexample, R^(5b) may be —OC(O)OCH₂-phenyl or —OC(O)CH₂—O-phenyl, andR^(5c) is H. Therefore, examples of R⁵ include—CH₂—C(O)NH[OC(O)OCH₂-phenyl] and —CH₂—C(O)N[OC(O)—CH₂O-phenyl]H. Inanother embodiment, R^(5b) is —OC(S)NR^(5bb)R^(5bc), where R^(5bb) andR^(5bc) are both —C₁₋₄alkyl, for example, R^(5b) may be —O—C(S)N(CH₃)₂.In another embodiment, R^(5b) is —OC(S)NR^(5bb)R^(5bc) and R^(5c) is H,for example, R⁵ may be —CH₂—C(O)N[OC(S)N(CH₃)₂]H.

In one particular embodiment, R⁵ is selected from —C₀₋₃alkylene-SR^(5a)and —C₀₋₃alkylene-C(O)NR^(5b)R^(5c); where R^(5a) is selected from H and—C(O)—C₁₋₆alkyl; R^(5b) is selected from H, —OH, and —OC(O)—C₁₋₆alkyl;and R^(5c) is selected from H and —C₁₋₆alkyl.

In one embodiment, R⁵ is —C₀₋₃alkylene-R^(5b)—C(O)R^(5d). R^(5d) is H,—C₁₋₄alkyl, —C₀₋₃alkylenearyl, —NR^(5da)R^(5db), —CH₂SH, or—O—C₁₋₆alkyl. The R^(5da) and R^(5db) moieties are independentlyselected from H and —C₁₋₄alkyl. In another embodiment, R^(5b) is —OH andR^(5d) is H, for example, R⁵ may be —CH₂—N(OH)C(O)H. In anotherembodiment, R^(5b) is —OH and R^(5d) is —C₁₋₄alkyl, for example, R⁵ maybe —CH₂—N(OH)C(O)CH₃. In another embodiment, R^(5b) is H and R^(5d) is—CH₂SH, for example, R⁵ may be —NHC(O)CH₂SH or —CH₂NHC(O)—CH₂SH.

In yet another embodiment, R⁵ is —NH—C₀₋₁alkylene-P(O)(OR^(5e))₂. TheR^(5e) moiety is H, —C₁₋₆alkyl, —C₁₋₃alkylenearyl,—C₁₋₃alkyleneheteroaryl, —C₃₋₇cycloalkyl, —CH(CH₃)—O—C(O)R^(5ea),

The R^(5ea) group is —O—C₁₋₆alkyl, —O—C₃₋₇cycloalkyl, —NR^(5eb)R^(5ec),or —CH(NH₂)CH₂COOCH₃. R^(5eb) and R^(5ec) are independently selectedfrom H, —C₁₋₄alkyl, and —C₁₋₃alkylenearyl (for example, benzyl). R^(5eb)and R^(5ec) may also be taken together to form —(CH₂)₃₋₆—. In oneembodiment, R^(5e) is H, for example, R⁵ may be —NH—CH₂—P(O)(OH)₂.

In one embodiment, R⁵ is —C₀₋₃alkylene-P(O)OR^(5e)R^(5f). The R^(5f)moiety is H, —C₁₋₄alkyl, —C₀₋₃alkylenearyl,—C₁₋₃alkylene-NR^(5f)R^(5fb), or—C₁₋₃alkylene(aryl)-C₀₋₃alkylene-NR^(5fa)R^(5fb). The R^(5fa) andR^(5fb) groups are independently selected from H and —C₁₋₄alkyl.

In one embodiment, R⁵ is —C₀₋₂alkylene-CHR^(5g)—COOH. The R^(5g) moietyis H, —C₁₋₆alkyl, —C₁₋₃alkylenearyl, or —CH₂—O—(CH₂)₂—OCH₃. In oneembodiment, R^(5g) is —CH₂—O—(CH₂)₂—OCH₃, for example, R⁵ may be—CH₂—C[CH₂—O—(CH₂)₂—OCH₃]H—COOH.

In another embodiment, R^(5g) is H, for example, R⁵ may be —CH₂COOH.

In one embodiment, R⁵ is —C₀₋₃alkylene-C(O)NR^(5h)—CHR^(5i)—COOH. TheR^(5h) moiety is H or —C₁₋₄alkyl. The R^(5i) moiety is H, —C₁₋₄alkyl, or—C₀₋₃alkylenearyl. In one embodiment, R^(5h) is H and R^(5i) is—C₀₋₃alkylenearyl, and the aryl is optionally substituted with 1 to 3substituents such as —OH, for example, R⁵ may be—C(O)NH—CH(CH₂-phenyl-OH)(COOH).

In one embodiment, R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d).More particularly, in one embodiment, R⁵ is selected from—C₀₋₁alkylene-SH, —C₀₋₁alkylene-C(O)N(OH)H, and—C₀₋₃alkylene-N(OH)—C(O)H. In another embodiment, R⁵ is selected from—C₀₋₃alkylene-SR^(5a) and —C₀₋₃alkylene-C(O)NR^(5b)R^(5c), where R^(5a)is H; R^(5b) is —OH. In one particular embodiment, R^(5c) is H.

In yet another embodiment, R⁵ is selected from—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)C(O)R^(5d);where R^(5a) is selected from —C(O)—C₁₋₆alkyl,—C(O)—C₀₋₆alkylene-C₃₋₇cycloalkyl, —C(O)—C₀₋₆alkylenearyl,—C(O)—C₀₋₆alkyleneheteroaryl, —C(O)—C₀₋₆alkylenemorpholine,—C(O)—C₀₋₆alkylenepiperazine-CH₃, —C(O)—CH(NH₂)-aa where aa is an aminoacid side chain, —C(O)-2-pyrrolidine, —C(O)—O—C₁₋₆alkyl,—C(O)—O—C₀₋₆alkylenearyl, —C₁₋₂alkylene-OC(O)—C₁₋₆alkyl,—C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, and—O—C₁₋₂alkylene-OC(O)O—C₁₋₆alkyl; and R^(5b) is selected from—OC(O)—C₁₋₆alkyl, —CH₂COOH, —O-benzyl, -pyridyl, —OC(O)O—CH₂-phenyl,—OC(O)CH₂—O-phenyl, —OC(O)N(CH₃)₂, and —OC(S)N(CH₃)₂. In one particularembodiment, R^(5c) or R^(5d) is H. In another particular embodiment,R^(5a) is selected from —C(O)—C₁₋₆alkyl,—C(O)—C₀₋₆alkylene-C₃₋₇cycloalkyl, —C(O)—C₀₋₆alkylenearyl, and—C(O)—C₀₋₆alkyleneheteroaryl. In one aspect of the invention, thesecompounds may find particular utility as prodrugs or as intermediates inthe synthetic procedures described herein.

R⁶ is selected from —C₁₋₆alkyl, —CH₂—O—(CH₂)₂OCH₃,—C₁₋₆alkylene-O—C₁₋₆alkyl, —C₀₋₃alkylenearyl, —C₀₋₃alkyleneheteroaryl,and —C₀₋₃alkylene-C₃₋₇cycloalkyl. In one particular embodiment, R⁶ isselected from —C₁₋₆alkyl, —C₀₋₃alkylenearyl, and—C₀₋₃alkylene-C₃₋₇cycloalkyl. Each alkyl and each aryl in R⁶ isoptionally substituted with 1 to 7 fluoro atoms, where the term “alkyl”is intended to include divalent alkylene groups such as those present in—C₁₋₆alkylene-O—C₁₋₆alkyl and —C₀₋₃alkylene-C₃₋₇cycloalkyl, for example.In addition, each aryl in R⁶ may be substituted with 1 to 3 —OH,—C₁₋₆alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl, —CN, halo, —O—C₁₋₆alkyl,—S—C₁₋₆alkyl, —S(O)—C₁₋₆alkyl, —S(O)₂—C₁₋₄alkyl, -phenyl, —NO₂, —NH₂,—NH—C₁₋₆alkyl, or —N(C₁₋₆alkyl)₂ groups. Further, each of theaforementioned alkyl, alkenyl and alkynyl groups may be substituted with1 to 5 fluoro atoms.

In one embodiment, R⁶ is —C₁₋₆alkyl, for example, —CH₃, —CH₂CH₃,—CH(CH₃)₂, —(CH₂)₂CH₃, —(CH₂)₃CH₃, —CH(CH₃)CH₂CH₃, —CH₂CH(CH₃)₂,—CH₂C(CH₃)₃, —(CH₂)₂CH(CH₃)₂, or —(CH₂)₄CH₃. As noted above, each alkylin R⁶ is optionally substituted with 1 to 7 fluoro atoms. Examples ofsuch fluoro-substituted R⁶ groups include —(CH₂)₂CF₃ and —(CH₂)₃CF₃.

In another embodiment, R⁶ is —CH₂O(CH₂)₂OCH₃. In still another oneembodiment, R⁶ is —C₁₋₆alkylene-O—C₁₋₆alkyl, for example, —OCH₃ and—CH₂OCH₃.

In one embodiment, R⁶ is —C₀₋₃alkylenearyl, for example, phenyl, benzyl,—CH₂-biphenyl, —(CH₂)₂-phenyl and —CH₂-naphthalen-1-yl. The aryl may besubstituted with 1 to 3 substituents. Thus, other examples of R⁶ includemono-substituted groups such as, methylbenzyl, chlorobenzyl,fluorobenzyl, fluorophenyl, bromobenzyl, iodobenzyl, -benzyl-CF₃,2-trifluoromethyl-benzyl, -benzyl-CN, and -benzyl-NO₂; anddi-substituted groups such as di-chlorobenzyl and di-fluorobenzyl. Eacharyl may also be substituted with 1 to 7 fluoro atoms. Thus, otherexamples of R⁶ include penta-fluorobenzyl.

In one embodiment, R⁶ is —C₀₋₃alkyleneheteroaryl, for example,—CH₂-pyridyl, —CH₂-furanyl, —CH₂-thienyl, and —CH₂-thiophenyl.

In another embodiment, R⁶ is —C₀₋₃alkylene-C₃₋₇cycloalkyl, for example,—CH₂-cyclopropyl, cyclopentyl, —CH₂-cyclopentyl, -cyclohexyl, and—CH₂-cyclohexyl.

R⁷ is H or is taken together with R⁶ to form —C₃₋₈cycloalkyl. In oneembodiment, R⁷ is H. In another embodiment, R⁷ is taken together with R⁶to form —C₃₋₈cycloalkyl, for example cyclopentyl.

In one particular embodiment, the compound of formula I is the speciesembodied in formula Ia:

and in one specific embodiment, Ar is selected from

and R¹, R³, X, and R⁵⁻⁶ are as defined for formula I; andpharmaceutically acceptable salts thereof. In another embodiment, thecompound of formula I is the species embodied in formula Ib:

and in one specific embodiment, Ar is selected from

and R¹, R³, and R⁵⁻⁶ are as defined for formula I; and pharmaceuticallyacceptable salts thereof. In yet another embodiment, the compound offormula I is the species embodied in formula Ic:

where R¹, R³, and R⁵⁻⁶ are as defined for formula I; andpharmaceutically acceptable salts thereof.

In one particular embodiment, R¹ is selected from —COOH, —SO₂NHR^(1d),and tetrazol-5-yl; and R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d);where R^(5a), R^(5c), and R^(5d) are H, and R^(5b) is —OH. In anotheraspect, this embodiment has formula Ia, Ib or Ic.

In one particular embodiment, R¹ is selected from —COOH, —SO₂NHR^(1d),and tetrazol-5-yl; and R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d);where R^(5a) is selected from —C(O)—C₁₋₆alkyl,—C(O)—C₀₋₆alkylene-C₃₋₇cycloalkyl, —C(O)—C₀₋₆alkylenearyl,—C(O)—C₀₋₆alkyleneheteroaryl, —C(O)—C₀₋₆alkylenemorpholine,—C(O)—C₀₋₆alkylenepiperazine-CH₃, —C(O)—CH(NH₂)-aa where aa is an aminoacid side chain, —C(O)-2-pyrrolidine, —C(O)—O—C₁₋₆alkyl,—C(O)—O—C₀₋₆alkylenearyl, —C₁₋₂alkylene-OC(O)—C₁₋₆alkyl,—C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, and—O—C₁₋₂alkylene-OC(O)—O—C₁₋₆alkyl; and R^(5b) is selected from—OC(O)—C₁₋₆alkyl, —CH₂COOH, —O-benzyl, -pyridyl, —OC(O)—O—CH₂-phenyl,—OC(O)CH₂—O-phenyl, —OC(O)N(CH₃)₂, and —OC(S)N(CH₃)₂. In another aspect,this embodiment has formula Ia, Ib or Ic. This embodiment may findparticular utility as an intermediate or as a prodrug.

In one particular embodiment, R¹ is —COOR^(1a) and R^(1a) is —C₁₋₆alkyl,—C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl, —C₃₋₇cycloalkyl,—CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,

and R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d);where R^(5a), R^(5c), and R^(5d) are H, and R^(5b) is —OH. In anotheraspect, this embodiment has formula Ia, Ib or Ic. This embodiment mayfind particular utility as an intermediate or as a prodrug.

In one particular embodiment, R¹ is —COOR^(1a) and R^(1a) is —C₁₋₆alkyl,—C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl, —C₃₋₇cycloalkyl,—CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,

and R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d);where R^(5a) is selected from —C(O)—C₁₋₆alkyl,—C(O)—C₀₋₆alkylene-C₃₋₇cycloalkyl, —C(O)—C₀₋₆alkylenearyl,—C(O)—C₀₋₆alkyleneheteroaryl, —C(O)—C₀₋₆alkylenemorpholine,—C(O)—C₀₋₆alkylenepiperazine-CH₃, —C(O)—CH(NH₂)-aa where aa is an aminoacid side chain, —C(O)-2-pyrrolidine, —C(O)—O—C₁₋₆alkyl,—C(O)—O—C₀₋₆alkylenearyl, —C₁₋₂alkylene-OC(O)—C₁₋₆alkyl,—C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, and—O—C₁₋₂alkylene-OC(O)O—C₁₋₆alkyl; and R^(5b) is selected from—OC(O)—C₁₋₆alkyl, —CH₂COOH, —O-benzyl, -pyridyl, —OC(O)O—CH₂-phenyl,—OC(O)CH₂—O-phenyl, —OC(O)N(CH₃)₂, and —OC(S)N(CH₃)₂. In another aspect,this embodiment has formula Ia, Ib or Ic. This embodiment may findparticular utility as an intermediate or as a prodrug.

Another embodiment of the invention provides for an active compound offormula I where Ar**—COOH represents Ar—R¹ and R⁵ is —C₀₋₃alkylene-SH.One corresponding prodrug (prodrug A) can contain a thioester linkage,which can be cleaved in vivo to form the —COOH(R¹) and—C₀₋₃alkylene-SH(R⁵) moieties. Another corresponding prodrug (prodrug B,where Z is —C₁₋₆alkylene, optionally substituted with one or moremoieties such as hydroxyl, phenyl, carboxyl, and so forth), containsboth an ester and a thioester group, which can be similarly cleaved invivo, but which also releases a physiologically acceptable acid such asα-hydroxy acid (Z is —CH₂—), β-hydroxy acid (Z is —(CH₂)₂—),(R)-2-hydroxypropionic or lactic acid (Z is —CH(CH₃)—),(R)-hydroxyphenylacetic or mandelic acid (Z is —CH(phenyl)-), salicylicacid (Z is -phenylene-), 2,3-dihydroxysuccinic or tartaric acid (Z is—CH(COOH)—CH(OH)—), citric acid (Z is —CH₂—C(CH₂—COOH)₂—), hydroxy bis-and hydroxy-tris acids, and so forth.

In one particular embodiment, the compound of formula I is the speciesembodied in formula Ia, wherein: Ar is an aryl group selected from:

R¹ is selected from —COOR^(1a), —SO₂NHR^(1d), and tetrazol-5-yl; whereR^(1a) is selected from H and —C₁₋₆alkyl; R^(1d) is —C(O)R^(1c); andR^(1c) is —C₁₋₆alkyl; R³ is selected from —C₁₋₁₀alkyl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, —C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b),—C₀₋₅alkylene-O—C₀₋₅alkylene-R^(3b), and —C₀₋₃alkylenearyl; where R^(3a)is H; and R^(3b) is selected from H, —C₁₋₆alkyl, and phenyl; X is—C₂₋₁₁alkylene-, where 1, 2 or 3 —CH₂— moieties in the alkylene arereplaced with a —NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety, where R^(4a) isH; R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₁alkylene-NHC(O)CH₂SH; whereR^(5a) is selected from H and —C(O)—C₁₋₆alkyl; R^(5b) is selected from—OH and —OC(O)—C₁₋₆alkyl; and R^(5c) is H; R⁶ is selected from—C₁₋₆alkyl, —C₀₋₃alkylenearyl, and —C₀₋₃alkylene-C₃₋₇Cycloalkyl; eachcarbon atom in X is optionally substituted with one or two R^(4b) groupsselected from —C₀₋₅alkylene-COOR^(4c) and —C₁₋₆alkyl, where R^(4c) is H;and pharmaceutically acceptable salts thereof. Each alkyl and each arylin R¹, R³, and R⁵⁻⁶ as well as each ring in Ar and each aryl in R¹, R³,and R⁵⁻⁶ are optionally substituted as described above for formula I.

In yet another embodiment, the compound of formula I is the speciesembodied in formula Ia, wherein: Ar is:

R¹ is selected from —SO₂NHR^(1d) and tetrazol-5-yl; where R^(1d) is—C(O)R^(1c) and R^(1c) is —C₁₋₆alkyl; R³ is selected from —C₂₋₅alkyl and—C₀₋₁alkylene-C₃₋₅cycloalkyl; X is —C₂₋₅alkylene-, where 1 or 2 —CH₂—moieties in the alkylene are replaced with a —NR^(4a)—C(O)— or—C(O)—NR^(4a) moiety, where R^(4a) is H; R⁵ is selected from—C₀₋₃alkylene-SR^(5a) and —C₀₋₃alkylene-C(O)NR^(5b)R^(5c); where R^(5a)is selected from H and —C(O)—C₁₋₆alkyl; R^(5b) is selected from —OH and—OC(O)—C₁₋₆alkyl; and R^(5c) is H; R⁶ is selected from —C₁₋₆alkyl,—C₀₋₃alkylenearyl, and —C₀₋₃alkylene-C₃₋₇cycloalkyl; one carbon atom inX is optionally substituted with one R^(4b) group selected from —COOHand —C₁₋₃alkyl; and pharmaceutically acceptable salts thereof. Eachalkyl and each aryl in R¹, R³, R^(4a-4d), and R⁵⁻⁶ as well as each ringin Ar and each aryl in R¹, R³, and R⁵⁻⁶ are optionally substituted asdescribed above for formula I.

In yet another embodiment, the compound of formula I is the speciesembodied in formula Id:

wherein: R^(1d) is —C(O)R^(1c); R^(1c) is —C₁₋₆alkyl or—C₀₋₆alkylene-O—R^(1ca); R^(1ca) is H; R³ is —C₁₋₁₀alkyl; X is—(CH₂)₂—NHC(O)— or —(CH₂)₂—C(O)NH—; and R⁶ is selected from —C₁₋₆alkyl,—C₀₋₃alkylenearyl, and —C₀₋₃alkylene-C₃₋₇cycloalkyl; andpharmaceutically acceptable salts thereof. In addition, each alkyl andeach aryl in R^(1d), R³, and R⁶ as well as each ring in Ar and each arylin R⁶ are optionally substituted as described above for formula I. Inone particular embodiment, one ring in Ar is optionally substituted with1-2 halo groups, and in another embodiment substituted with one halogroup such as fluoro. In another embodiment, the aryl in R⁶ isoptionally substituted with a halo group. In one exemplary embodiment,the compounds of formula Id have the (R) configuration at the R⁶ carbonas shown in formula Id′:

In another exemplary embodiment, the compounds of formula Id, whereR^(1d) is —C(O)CH₃ or —C(O)—CH(CH₃)OH; and R⁶ is i-butyl, benzyl,-2-fluorobenzyl, -3-chlorobenzyl, or cyclohexyl.

A particular group of compounds of formula I are those disclosed in U.S.Provisional Application No. 60/899,264, filed on Feb. 2, 2007 and No.60/901,531, filed on Feb. 15, 2007. This group includes compounds offormula I′:

wherein: r is 0, 1 or 2; Ar′ is an aryl group selected from:

R¹′ is selected from —COOR^(1a)′, —NHSO₂C₁₋₆alkyl, —NHSO₂aryl,—NHSO₂NH—C(O)—C₁₋₆alkyl, —NHSO₂NH—C(O)-aryl, —SO₂NH—C(O)—C₁₋₆alkyl,—SO₂NH—C(O)—C₁₋₆aryl, —SO₂NH—C(O)—NH—C₁₋₆alkyl, —SO₂NH—C(O)—NH-aryl,—SO₂OH, —SO₂NH₂, —SO₂NH—C₁₋₆alkyl, —SO₂NH—C₁₋₆aryl,—C(O)—NH—SO₂—C₁₋₆alkyl, —C(O)—NH—SO₂-aryl, —P(O)(OH)₂, —CN,—O—CH(CH₃)—COOH, —O—CH(aryl)-COOH, tetrazol-5-yl,

where R^(1a)′ is selected from H, —C₁₋₆alkyl, benzyl,—C₁₋₃alkylene-heteroaryl, cycloalkyl, —CH(CH₃)OC(O)R^(1b)′,

R^(1b)′ is selected from —O—C₁₋₆alkyl, —O-cycloalkyl, —NR^(1c)′R^(1d)′,—CH(NH₂)CH₂COOCH₃; and R^(1c)′ and R^(1d)′ are independently selectedfrom H, —C₁₋₆alkyl, and benzyl, or are taken together as —(CH₂)₃₋₆—;

R³′ is selected from —C₁₋₁₀alkyl, —C₂₋₁₀alkenyl, —C₃₋₁₀alkynyl,—C₃₋₇cycloalkyl, —C₀₋₃alkylene-C₃₋₇cycloalkyl,—C₀₋₃alkenylene-C₃₋₇cycloalkyl, —C₀₋₃alkynylene-C₃₋₇cycloalkyl,—(CH₂)₀₋₅NR^(3c)′(CH₂)₀₋₅R^(3b)′, —(CH₂)₀₋₅O(CH₂)₁₋₅R^(3b)′,—(CH₂)₁₋₅S(CH₂)₁₋₅R^(3b)′, and —C₀₋₃alkylenephenyl; where R^(3b)′ isselected from H, —C₁₋₆alkyl, —C₃₋₆cycloalkyl, —C₂₋₄alkenyl,—C₂₋₄alkynyl, and phenyl; and R^(3c)′ is selected from H, —C₁₋₆alkyl,—C₃₋₆cycloalkyl, phenyl, and benzyl;

R⁴′ is selected from —X—CHR⁵′R⁶′ and

X′ is C₁₋₂alkylene, where at least one —CH₂— moiety in the alkylene isreplaced with a —NR^(4a)′—C(O)— or —C(O)—NR^(4a)′— moiety, where R^(4a)′is selected from H, —OH, and —C₁₋₄alkyl;

R⁵′ is selected from —C₀₋₃alkylene-SR^(5a)′,—C₀₋₃alkylene-C(O)NR^(5b)′R^(5c)′, —C₀₋₃alkylene-NR^(5b)′—C(O)R^(5d)′,—C₀₋₁alkylene-NHC(O)CH₂SH, —NH—C₀₋₁alkylene-P(O)(OH)₂, and—C₀₋₂alkylene-COOH; where R^(5a)′ is selected from H, —C(O)—C₁₋₆alkyl,—C(O)—C₀₋₆alkylene-cycloalkyl, —C(O)—C₀₋₆alkylene-aryl, and—C(O)—C₀₋₆alkylene-heteroaryl; R^(5b)′ is selected from H, —OH,—OC(O)C₁₋₆alkyl, —CH₂COOH, —O-benzyl, -pyridyl, —OC(O)O—CH₂-phenyl,—OC(O)CH₂O-phenyl, —OC(O)N(CH₃)₂, and —OC(S)N(CH₃)₂; R^(5c)′ is selectedfrom H, —C₁₋₆alkyl, and —C(O)—R^(5e)′, where R^(5e)′ is selected from—C₁₋₆alkyl, —C₃₋₇cycloalkyl, aryl, and heteroaryl; and R^(5d)′ isselected from H, —C₁₋₄alkyl, —C₀₋₃alkylenearyl, —N^(5f)′R^(5g)′, and—O—C₁₋₆alkyl, where R^(5f)′ and R^(5g)′ are independently selected fromH and —C₁₋₄alkyl; and

R⁶′ is selected from —C₁₋₆alkyl, —CH₂O(CH₂)₂OCH₃,—C₁₋₆alkylene-O—C₁₋₆alkyl, —C₀₋₃alkylene-aryl, —C₀₋₃alkylene-heteroaryl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, and biphenyl;

wherein: each —CH₂— group in —(CH₂)_(r)— is optionally substituted with1 or 2 substituents independently selected from —C₁₋₄alkyl and fluoro;each ring in Ar is optionally substituted with 1 to 3 substituentsindependently selected from —OH, —C₁₋₄alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl,—CN, halo, —O(C₁₋₄alkyl), —S(C₁₋₄alkyl), —S(O)(C₁₋₄alkyl),—S(O)₂(C₁₋₄alkyl), -phenyl, —NH₂, —NH(C₁₋₄alkyl) and —N(C₁₋₄alkyl)₂,wherein each alkyl, alkenyl and alkynyl group is optionally substitutedwith 1 to 5 fluoro atoms; each alkyl in R¹′ and R^(5e)′ is optionallysubstituted with 1 to 7 fluoro atoms; each benzyl group in R^(1a)′ isoptionally substituted with fluoro, —CF₃ or —O—CF₃; each alkyl, alkenyl,alkynyl, —(CH₂)₀₋₅NR^(3c)′(CH₂)₀₋₅R^(3b)′, —(CH₂)₁₋₅O(CH₂)₁₋₅R^(3b)′,and —(CH₂)₁₋₅S(CH₂)₁₋₅R^(3b)′ group in R³′ is optionally substitutedwith —COOR^(3a)′ and/or 1 to 9 fluoro atoms, where R^(3a)′ is selectedfrom H, —C₁₋₈ perfluoroalkyl, —C₃₋₆cycloalkyl, phenyl and benzyl; the—C₀₋₃alkylenephenyl group in R³′ is optionally substituted on the phenylring with 1 to 2 halo, —C₁₋₄alkyl, —C₁₋₄alkoxy, —OH, or —NO₂ groups;each carbon atom in the alkylene moiety in X′ is optionally substitutedwith one more R^(4b)′ groups and one —CH₂— moiety in X′ may be replacedwith —C₄₋₈cycloalkylene; wherein R^(4b)′ is selected from—C₀₋₅alkylene-COOH, —C₁₋₆alkyl, —C₀₋₁alkylene-CONH₂, —C₁₋₂alkylene-OH,—C₀₋₃alkylene-C₃₋₇cycloalkyl, and benzyl; the aryl in R^(5a), isoptionally substituted with 1 to 3 groups selected from —C₁₋₄alkyl,—C₁₋₄alkoxy, —C₁₋₄alkylthio, —OH, —Cl, —Br, —F, —NH₂, —NH—C₁₋₄alkyl,—N(C₁₋₄alkyl)₂, —NO₂ and —CF₃; the alkyl in R⁶′ is optionallysubstituted with 1 to 7 halo atoms; and each aryl in R¹′ and R⁶′, andthe benzyl group in R^(1a)′ is optionally substituted with one or more—C₁₋₆alkyl, —C₁₋₆alkoxy, halo, phenyl, trifluoromethyl, —NO₂, —CN or —OHgroups; or a pharmaceutically acceptable salt thereof. In anotherembodiment, R⁷′ is selected from —C₁₋₂alkylene-CHR^(7a)—COOH and—C₀₋₃alkylene-C(O)NR^(7b)′—CHR^(7c)′—COOH, where R^(7a)′ is selectedfrom H, —C₁₋₉alkyl, and —CH₂—O—(CH₂)₂—OCH₃; R^(7b)′ is selected from Hand —C₁₋₄alkyl; and R^(7c)′ is selected from H, —C₁₋₄alkyl, andhydroxybenzyl.

In addition, compounds of formula I that are of particular interestinclude those set forth in the Examples below, as well as thepharmaceutically acceptable salts thereof.

DEFINITIONS

When describing the compounds, compositions, methods and processes ofthe invention, the following terms have the meanings set forth below,unless indicated otherwise. Additionally, as used herein, the singularforms “a,” “an,” and “the” include the corresponding plural forms unlessthe context of use clearly dictates otherwise. The terms “comprising”,“including,” and “having” are intended to be inclusive and mean thatthere may be additional elements other than the listed elements.

The term “pharmaceutically acceptable” refers to a material that is notbiologically or otherwise undesirable. For example, the term“pharmaceutically acceptable carrier” refers to a material that can beincorporated into a composition and administered to a patient withoutcausing undesirable biological effects or interacting in a deleteriousmanner with other components of the composition. Such pharmaceuticallyacceptable materials typically have met the required standards oftoxicological and manufacturing testing, and include those materialsidentified as suitable inactive ingredients by the U.S. Food and Drugadministration.

The term “pharmaceutically acceptable salt” means a salt prepared from abase or an acid which is acceptable for administration to a patient,such as a mammal (for example, salts having acceptable mammalian safetyfor a given dosage regime). However, it is understood that the saltscovered by the invention are not required to be pharmaceuticallyacceptable salts, such as salts of intermediate compounds that are notintended for administration to a patient. Pharmaceutically acceptablesalts can be derived from pharmaceutically acceptable inorganic ororganic bases and from pharmaceutically acceptable inorganic or organicacids. In addition, when a compound of formula I contains both a basicmoiety, such as an amine, pyridine or imidazole, and an acidic moietysuch as a carboxylic acid or tetrazole, zwitterions may be formed andare included within the term “salt” as used herein. Salts derived frompharmaceutically acceptable inorganic bases include ammonium, calcium,copper, ferric, ferrous, lithium, magnesium, manganic, manganous,potassium, sodium, and zinc salts, and the like. Salts derived frompharmaceutically acceptable organic bases include salts of primary,secondary and tertiary amines, including substituted amines, cyclicamines, naturally-occurring amines and the like, such as arginine,betaine, caffeine, choline, N,N′-dibenzylethylenediamine, diethylamine,2-diethylaminoethanol, 2-dimethylaminoethanol, ethanolamine,ethylenediamine, N-ethylmorpholine, N-ethylpiperidine, glucamine,glucosamine, histidine, hydrabamine, isopropylamine, lysine,methylglucamine, morpholine, piperazine, piperadine, polyamine resins,procaine, purines, theobromine, triethylamine, trimethylamine,tripropylamine, tromethamine and the like. Salts derived frompharmaceutically acceptable inorganic acids include salts of boric,carbonic, hydrohalic (hydrobromic, hydrochloric, hydrofluoric orhydroiodic), nitric, phosphoric, sulfamic and sulfuric acids. Saltsderived from pharmaceutically acceptable organic acids include salts ofaliphatic hydroxyl acids (for example, citric, gluconic, glycolic,lactic, lactobionic, malic, and tartaric acids), aliphaticmonocarboxylic acids (for example, acetic, butyric, formic, propionicand trifluoroacetic acids), amino acids (for example, aspartic andglutamic acids), aromatic carboxylic acids (for example, benzoic,p-chlorobenzoic, diphenylacetic, gentisic, hippuric, and triphenylaceticacids), aromatic hydroxyl acids (for example, o-hydroxybenzoic,p-hydroxybenzoic, 1-hydroxynaphthalene-2-carboxylic and3-hydroxynaphthalene-2-carboxylic acids), ascorbic, dicarboxylic acids(for example, fumaric, maleic, oxalic and succinic acids), glucoronic,mandelic, mucic, nicotinic, orotic, pamoic, pantothenic, sulfonic acids(for example, benzenesulfonic, camphosulfonic, edisylic, ethanesulfonic,isethionic, methanesulfonic, naphthalenesulfonic,naphthalene-1,5-disulfonic, naphthalene-2,6-disulfonic andp-toluenesulfonic acids), xinafoic acid, and the like.

As used herein, the term “prodrug” is intended to mean an inactive (orsignificantly less active) precursor of a drug that is converted intoits active form in the body under physiological conditions, for example,by normal metabolic processes. The term is also intended to includecertain protected derivatives of compounds of formula I that may be madeprior to a final deprotection stage. Such compounds may not possesspharmacological activity at AT₁ and/or NEP, but may be administeredorally or parenterally and thereafter metabolized in the body to formcompounds of the invention which are pharmacologically active at AT₁and/or NEP. Thus, all protected derivatives and prodrugs of compoundsformula I are included within the scope of the invention. Prodrugs ofcompounds of formula I having a free carboxyl, sulfhydryl or hydroxygroup can be readily synthesized by techniques that are well known inthe art. These prodrug derivatives are then converted by solvolysis orunder physiological conditions to be the free carboxyl, sulfhydryland/or hydroxy compounds. Exemplary prodrugs include: esters includingC₁₋₆alkylesters and aryl-C₁₋₆alkylesters, carbonate esters, hemi-esters,phosphate esters, nitro esters, sulfate esters, sulfoxides, amides,carbamates, azo-compounds, phosphamides, glycosides, ethers, acetals andketals. In one embodiment, the compounds of formula I have a freesulfhydryl or a free carboxyl and the prodrug is an ester derivative.

The term “solvate” means a complex or aggregate formed by one or moremolecules of a solute, for example, a compound of formula I or apharmaceutically acceptable salt thereof, and one or more molecules of asolvent. Such solvates are typically crystalline solids having asubstantially fixed molar ratio of solute and solvent. Representativesolvents include, by way of example, water, methanol, ethanol,isopropanol, acetic acid and the like. When the solvent is water, thesolvate formed is a hydrate.

The term “therapeutically effective amount” means an amount sufficientto effect treatment when administered to a patient in need thereof, thatis, the amount of drug needed to obtain the desired therapeutic effect.For example, a therapeutically effective amount for treatinghypertension could be the amount of drug needed to reduce blood pressureor the amount of drug needed to maintain normal blood pressure. On theother hand, the term “effective amount” means an amount sufficient toobtain a desired result, which may not necessarily be a therapeuticresult. For example, when studying a system comprising an AT₁ receptor,an “effective amount” may be the amount needed to antagonize thereceptor.

The term “treating” or “treatment” as used herein means the treating ortreatment of a disease or medical condition (such as hypertension) in apatient, such as a mammal (particularly a human) that includes: (a)preventing the disease or medical condition from occurring, such asprophylactic treatment of a patient; (b) ameliorating the disease ormedical condition such as by eliminating or causing regression of thedisease or medical condition in a patient; (c) suppressing the diseaseor medical condition such as by slowing or arresting the development ofthe disease or medical condition in a patient; or (d) alleviating thesymptoms of the disease or medical condition in a patient. For example,the term “treating hypertension” includes preventing hypertension fromoccurring, ameliorating hypertension, suppressing hypertension, andalleviating the symptoms of hypertension (for example, lowering bloodpressure). The term “patient” is intended to include those mammals, suchas humans, that are in need of treatment or disease prevention or thatare presently being treated for disease prevention or treatment of aspecific disease or medical condition. The term “patient” also includestest subjects in which compounds of the invention are being evaluated ortest subjects being used in a assay, for example an animal model.

The term “alkyl” means a monovalent saturated hydrocarbon group whichmay be linear or branched. Unless otherwise defined, such alkyl groupstypically contain from 1 to 10 carbon atoms and include, for example,—C₁₋₄alkyl, —C₁₋₆alkyl, and —C₁₋₁₀alkyl. Representative alkyl groupsinclude, by way of example, methyl, ethyl, n-propyl, isopropyl, n-butyl,s-butyl, isobutyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl,n-nonyl, n-decyl and the like.

When a specific number of carbon atoms is intended for a particular termused herein, the number of carbon atoms is shown preceding the term assubscript. For example, the term “—C₁₋₆alkyl” means an alkyl grouphaving from 1 to 6 carbon atoms, and the term “—C₃₋₇cycloalkyl” means acycloalkyl group having from 3 to 7 carbon atoms, where the carbon atomsare in any acceptable configuration.

The term “alkylene” means a divalent saturated hydrocarbon group thatmay be linear or branched. Unless otherwise defined, such alkylenegroups typically contain from 0 to 12 carbon atoms and include, forexample, —C₀₋₁alkylene-, —C₀₋₂alkylene-, —C₀₋₃alkylene-, —C₀₋₅alkylene-,—C₀₋₆alkylene-, —C₁₋₂alkylene- and —C₁₋₂alkylene-. Representativealkylene groups include, by way of example, methylene, ethane-1,2-diyl(“ethylene”), propane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl,pentane-1,5-diyl and the like. It is understood that when the alkyleneterm include zero carbons such as —C₀₋₁alkylene- or —C₀₋₅alkylene-, suchterms are intended to include a single bond.

The term “alkylthio” means a monovalent group of the formula —S-alkyl,where alkyl is as defined herein. Unless otherwise defined, suchalkylthio groups typically contain from 1 to 10 carbon atoms andinclude, for example, —S—C₁₋₄alkyl and —S—C₁₋₆alkyl. Representativealkylthio groups include, by way of example, ethylthio, propylthio,isopropylthio, butylthio, s-butylthio and t-butylthio.

The term “alkenyl” means a monovalent unsaturated hydrocarbon groupwhich may be linear or branched and which has at least one, andtypically 1, 2 or 3, carbon-carbon double bonds. Unless otherwisedefined, such alkenyl groups typically contain from 2 to 10 carbon atomsand include, for example, —C₂₋₄alkenyl and —C₂₋₁₀alkenyl. Representativealkenyl groups include, by way of example, ethenyl, n-propenyl,isopropenyl, n-but-2-enyl, n-hex-3-enyl and the like. The term“alkenylene” means a divalent alkenyl group, and includes groups such as—C₂₋₃alkenylene-.

The term “alkoxy” means a monovalent group of the formula —O-alkyl,where alkyl is as defined herein. Unless otherwise defined, such alkoxygroups typically contain from 1 to 10 carbon atoms and include, forexample, —O—C₁₋₄alkyl and —O—C₁₋₆alkyl. Representative alkoxy groupsinclude, by way of example, methoxy, ethoxy, n-propoxy, isopropoxy,n-butoxy, sec-butoxy, isobutoxy, t-butoxy and the like.

The term “alkynyl” means a monovalent unsaturated hydrocarbon groupwhich may be linear or branched and which has at least one, andtypically 1, 2 or 3, carbon-carbon triple bonds. Unless otherwisedefined, such alkynyl groups typically contain from 2 to 10 carbon atomsand include, for example, —C₂₋₄alkynyl and —C₃₋₁₀alkynyl. Representativealkynyl groups include, by way of example, ethynyl, n-propynyl,n-but-2-ynyl, n-hex-3-ynyl and the like. The term “alkynylene” means adivalent alkynyl group and includes groups such as —C₂₋₃alkynylene-.

Amino acid residues are often designated as —C(O)—CHR—NH—, where the Rmoiety is referred to as the “amino acid side chain.” Thus, for theamino acid valine, HO—C(O)—CH[—CH(CH₃)₂]—NH₂, the side chain is—CH(CH₃)₂. The term “amino acid side chain” is intended to include sidechains of the twenty common naturally occurring amino acids: alanine,arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine,glycine, histidine, isoleucine, leucine, lysine, methionine,phenylalanine, proline, serine, threonine, tryptophan, tyrosine, andvaline. Of particular interest are the side chains of non-polar aminoacids such as isoleucine, leucine, and valine.

The term “aryl” means a monovalent aromatic hydrocarbon having a singlering (for example, phenyl) or fused rings. Fused ring systems includethose that are fully unsaturated (for example, naphthalene) as well asthose that are partially unsaturated (for example,1,2,3,4-tetrahydronaphthalene). Unless otherwise defined, such arylgroups typically contain from 6 to 10 carbon ring atoms and include, forexample, —C₆₋₁₀aryl. Representative aryl groups include, by way ofexample, phenyl and naphthalene-1-yl, naphthalene-2-yl, and the like.The term “arylene” means a divalent aryl group such as phenylene.

The term “cycloalkyl” means a monovalent saturated carbocyclichydrocarbon group. Unless otherwise defined, such cycloalkyl groupstypically contain from 3 to 10 carbon atoms and include, for example,—C₃₋₅cycloalkyl, —C₃₋₆cycloalkyl and —C₃₋₇cycloalkyl. Representativecycloalkyl groups include, by way of example, cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl and the like. The term “cycloalkylene” means adivalent aryl group such as —C₄₋₈cycloalkylene.

The term “halo” means fluoro, chloro, bromo and iodo.

The term “heteroaryl” means a monovalent aromatic group having a singlering or two fused rings and containing in the ring(s) at least oneheteroatom (typically 1 to 3) selected from nitrogen, oxygen or sulfur.Unless otherwise defined, such heteroaryl groups typically contain from5 to 10 total ring atoms and include, for example, —C₂₋₉heteroaryl.Representative heteroaryl groups include, by way of example, monovalentspecies of pyrrole, imidazole, thiazole, oxazole, furan, thiophene,triazole, pyrazole, isoxazole, isothiazole, pyridine, pyrazine,pyridazine, pyrimidine, triazine, indole, benzofuran, benzothiophene,benzoimidazole, benzthiazole, quinoline, isoquinoline, quinazoline,quinoxaline and the like, where the point of attachment is at anyavailable carbon or nitrogen ring atom.

The term “optionally substituted” means that group in question may beunsubstituted or it may be substituted one or several times, such as 1to 3 times or 1 to 5 times. For example, an alkyl group that is“optionally substituted” with 1 to 5 fluoro atoms, may be unsubstituted,or it may contain 1, 2, 3, 4, or 5 fluoro atoms.

The term “protected derivatives thereof” means a derivative of thespecified compound in which one or more functional groups of thecompound are protected or blocked from undergoing undesired reactionswith a protecting or blocking group. Functional groups that may beprotected include, by way of example, carboxy groups, amino groups,hydroxyl groups, thiol groups, carbonyl groups and the like.Representative protecting groups for carboxy groups include esters (suchas a p-methoxybenzyl ester), amides and hydrazides; for amino groups,carbamates (such as t-butoxycarbonyl) and amides; for hydroxyl groups,ethers and esters; for thiol groups, thioethers and thioesters; forcarbonyl groups, acetals and ketals; and the like. Such protectinggroups are well known to those skilled in the art and are described, forexample, in T. W. Greene and G. M. Wuts, Protective Groups in OrganicSynthesis, Third Edition, Wiley, New York, 1999, and references citedtherein.

All other terms used herein are intended to have their ordinary meaningas understood by those of ordinary skill in the art to which theypertain.

General Synthetic Procedures

Compounds of the invention can be prepared from readily availablestarting materials using the following general methods, the proceduresset forth in the Examples, or by using other methods, reagents, andstarting materials that are known to those of ordinary skill in the art.Although the following procedures may illustrate a particular embodimentof the invention, it is understood that other embodiments of theinvention can be similarly prepared using the same or similar methods orby using other methods, reagents and starting materials known to thoseof ordinary skill in the art. It will also be appreciated that wheretypical or preferred process conditions (for example, reactiontemperatures, times, mole ratios of reactants, solvents, pressures,etc.) are given, other process conditions can also be used unlessotherwise stated. While optimum reaction conditions will typically varydepending on various reaction parameters such as the particularreactants, solvents and quantities used, those of ordinary skill in theart can readily determine suitable reaction conditions using routineoptimization procedures.

Additionally, as will be apparent to those skilled in the art,conventional protecting groups may be necessary or desired to preventcertain functional groups from undergoing undesired reactions. Thechoice of a suitable protecting group for a particular functional groupas well as suitable conditions and reagents for protection anddeprotection of such functional groups are well known in the art.Protecting groups other than those illustrated in the proceduresdescribed herein may be used, if desired. For example, numerousprotecting groups, and their introduction and removal, are described inT. W. Greene and G. M. Wuts, Protective Groups in Organic Synthesis,supra. More specifically, the following abbreviations and reagents areused in the schemes presented below:

P¹ represents an “amino-protecting group,” a term used herein to mean aprotecting group suitable for preventing undesired reactions at an aminogroup. Representative amino-protecting groups include, but are notlimited to, t-butoxycarbonyl (BOC), trityl (Tr), benzyloxycarbonyl(Cbz), 9-fluorenylmethoxycarbonyl (Fmoc), formyl, trimethylsilyl (TMS),t-butyldimethylsilyl (TBDMS), and the like. Standard deprotectiontechniques are used to remove the P¹ group. For example, deprotection ofan N—BOC group can involve reagents such as TFA in DCM or HCl in1,4-dioxane, while a Cbz group can be removed by employing catalytichydrogenation conditions such as H₂ (1 atm), 10% Pd/C in an alcoholicsolvent.

P² represents a “carboxy-protecting group,” a term used herein to mean aprotecting group suitable for preventing undesired reactions at acarboxy group. Representative carboxy-protecting groups include, but arenot limited to, methyl, ethyl, t-butyl, benzyl (Bn), p-methoxybenzyl(PMB), 9-fluoroenylmethyl (Fm), trimethylsilyl (TMS),t-butyldimethylsilyl (TBDMS), diphenylmethyl (benzhydryl, DPM) and thelike. Standard deprotection techniques and reagents are used to removethe P² group, and may vary depending upon which group is used. Forexample, NaOH is commonly used when P² is methyl, an acid such as TFA orHCl is commonly used when P² is t-butyl, and catalytic hydrogenationconditions such as H₂ (1 atm) and 10% Pd/C in alcoholic solvent(“H₂/Pd/C”) may be used when P² is benzyl.

P³ represents a “thiol-protecting group,” a term used herein to mean aprotecting group suitable for preventing undesired reactions at a thiolgroup. Representative thiol-protecting groups include, but are notlimited to, ethers, esters such as, —C(O)CH₃, and the like. Standarddeprotection techniques and reagents such as NaOH, primary alkylamines,and hydrazine, may be used to remove the P³ group.

P⁴ represents a “tetrazole-protecting group,” a term used herein to meana protecting group suitable for preventing undesired reactions at atetrazole group. Representative tetrazole-protecting groups include, butare not limited to trityl, benzoyl and diphenylmethyl. Standarddeprotection techniques and reagents such as TFA in DCM or HCl in1,4-dioxane may be used to remove the P⁴ group.

P⁵ represents a “hydroxyl-protecting group,” a term used herein to meana protecting group suitable for preventing undesired reactions at ahydroxyl group. Representative hydroxyl-protecting groups include, butare not limited to C₁₋₆alkyl, silyl groups including triC₁₋₆alkylsilylgroups, such as trimethylsilyl (TMS), triethylsilyl (TES), andtert-butyldimethylsilyl (TBDMS); esters (acyl groups) includingC₁₋₆alkanoyl groups, such as formyl, acetyl, and pivaloyl, and aromaticacyl groups such as benzoyl; arylmethyl groups such as benzyl (Bn),p-methoxybenzyl (PMB), 9-fluorenylmethyl (Fm), and diphenylmethyl(benzhydryl, DPM); and the like. Standard deprotection techniques andreagents are used to remove the P⁵ group, and may vary depending uponwhich group is used. For example, H₂/Pd/C is commonly used when P⁵ isbenzyl, while NaOH is commonly used when P⁵ is an acyl group.

P⁶ represents a “sulfonamide-protecting group,” a term used herein tomean a protecting group suitable for preventing undesired reactions at asulfonamide group. Representative sulfonamide-protecting groups include,but are not limited to t-butyl and acyl groups. Exemplary acyl groupsinclude aliphatic lower acyl groups such as the formyl, acetyl,phenylacetyl, butyryl, isobutyryl, valeryl, isovaleryl and pivaloylgroups, and aromatic acyl groups such as the benzoyl and4-acetoxybenzoyl. Standard deprotection techniques and reagents are usedto remove the P⁶ group, and may vary depending upon which group is used.For example, HCl is commonly used when P⁶ is t-butyl, while NaOH iscommonly used when P⁶ is an acyl group.

P⁷ represents a “phosphonate-protecting group or phosphinate-protectinggroup,” a term used herein to mean a protecting group suitable forpreventing undesired reactions at a phosphonate or phosphinate group.Representative phosphonate and phosphinate protecting groups include,but are not limited to C₁₋₄alkyl, aryl (for example, phenyl) andsubstituted aryls (for example, chlorophenyl and methylphenyl). Theprotected group can be represented by —P(O)(OR)₂, where R is a groupsuch as a C₁₋₆alkyl or phenyl. Standard deprotection techniques andreagents such as TMS-I/2,6-lutidine and H₂/Pd/C are used to remove theP⁷ group such as ethyl, and benzyl, respectively.

In addition, L is used to designate a “leaving group,” a term usedherein to mean a functional group or atom which can be displaced byanother functional group or atom in a substitution reaction, such as anucleophilic substitution reaction. By way of example, representativeleaving groups include chloro, bromo and iodo groups; sulfonic estergroups, such as mesylate, triflate, tosylate, brosylate, nosylate andthe like; acyloxy groups, such as acetoxy, trifluoroacetoxy; formylgroups; and so forth.

Suitable bases for use in these schemes include, by way of illustrationand not limitation, potassium carbonate, calcium carbonate, sodiumcarbonate, triethylamine, pyridine, 1,8-diazabicyclo-[5.4.0]undec-7-ene(DBU), N,N-diisopropylethylamine (DIPEA), sodium hydroxide, potassiumhydroxide, potassium t-butoxide, and metal hydrides.

Suitable inert diluents or solvents for use in these schemes include, byway of illustration and not limitation, tetrahydrofuran (THF),acetonitrile (MeCN), N,N-dimethylformamide (DMF), dimethyl sulfoxide(DMSO), toluene, dichloromethane (DCM), chloroform (CHCl₃), carbontetrachloride (CCl₄), 1,4-dioxane, methanol, ethanol, water, and thelike.

Suitable carboxylic acid/amine coupling reagents includebenzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate(BOP), benzotriazol-1-yloxytris(dimethylamino)phosphoniumhexafluorophosphate (PyBOP),O-(7-azabenzotriazol-1-yl-N,N,N′,N′-tetramethyluroniumhexafluorophosphate (HATU), dicyclohexylcarbodiimide (DCC),N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC),carbonyldiimidazole (CDI), and the like. Coupling reactions areconducted in an inert diluent in the presence of a base, and areperformed under conventional amide bond-forming conditions.

All reactions are typically conducted at a temperature within the rangeof about −78° C. to 100° C., for example at room temperature. Reactionsmay be monitored by use of thin layer chromatography (TLC), highperformance liquid chromatography (HPLC), and/or LCMS until completion.Reactions may be complete in minutes, or may take hours, typically from1-2 hours and up to 48 hours. Upon completion, the resulting mixture orreaction product may be further treated in order to obtain the desiredproduct. For example, the resulting mixture or reaction product may besubjected to one or more of the following procedures: concentrating orpartitioning (for example, between EtOAc and water or between 5% THF inEtOAc and 1M phosphoric acid); extraction (for example, with EtOAc,CHCl₃, DCM, chloroform, HCl); washing (for example, with saturatedaqueous NaCl, saturated NaHCO₃, Na₂CO₃ (5%), CHCl₃ or 1M NaOH); drying(for example, over MgSO₄, over Na₂SO₄, or in vacuo); filtering;crystallizing (for example, from EtOAc and hexane); and/or beingconcentrated (for example, in vacuo).

By way of illustration, compounds of formula I, as well as their salts,solvates, and prodrugs can be prepared by one or more of the followingexemplary processes.

In the compounds of formula I, X is C₁₋₁₂alkylene, where at least one—CH₂— moiety in the alkylene is replaced with a —NR^(4a)—C(O)— or—C(O)—NR^(4a)— moiety. Step 1 is performed when a —CH₂— moiety in thealkylene is replaced with a —NR^(4a)C(O)— moiety. Step 1a is performedwhen a —CH₂— moiety in the alkylene is replaced with a —C(O)—NR^(4a)—moiety.

Step 1

Step 1a

Steps 1 and 1a are standard alkylation reactions and are typicallyconducted in the presence of a suitable base such as potassiumcarbonate.

Compound (1): Ar* represents Ar—R¹*, where R¹* may represent R¹ asdefined herein, or may represent a protected form of R¹ (for example,-tetrazol-5-yl-P⁴ or —C(O)O—P² such as —C(O)O—C₁₋₆alkyl), or mayrepresent a precursor of R¹ (for example, —CN or nitro that is thenconverted to amino, from which the desired R¹ is prepared). Examples ofcompound (1) include:

Compound (1) may be synthesized as follows:

The starting material can be prepared using synthetic methods that arereported in the literature, for example Duncia et al. (1991) J. Org.Chem. 56: 2395-400, and references cited therein. Alternatively, thestarting material in a protected form may be commercially available.Using a commercially available non-protected starting material, the R¹group is first protected, then the —(CH₂)_(r)-L¹ moiety is added, forexample, by a halogenation reaction with a material such asN-bromosuccinimide. For example, a bromination reaction of a methylgroup of N-triphenylmethyl-5-[4′-methylbiphenyl-2-yl]tetrazole isdescribed in Chao et al. (2005) J. Chinese Chem. Soc. 52:539-544.

In addition, when Ar* has a —CN group, it can be subsequently convertedto the desired tetrazolyl group, which may be protected. Conversion ofthe nitrile group is readily achieved by reaction with a suitable azidesuch as sodium azide, trialkyltin azide (particularly tributyltin azide)or triaryltin azide.

Compound (1) where R¹ is —SO₂NHR^(1d) may also be synthesized asfollows:

The starting material, 2-bromobenzenesulfonyl chloride, is commerciallyavailable. Reaction of 2-bromobenzenesulfonyl chloride in a solvent suchas DCM, with t-butylamine in the presence of a base such as DIPEA,yields 2-bromo-N-t-butylbenzenesulfonamide. This intermediate is thencoupled with 4-formylphenylboronic acid using Suzuki coupling reactionconditions, to provide compound (1). Representative catalysts includepalladium and nickel catalysts, such astetrakis(triphenylphosphine)palladium(0),[1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II),bis[1,2-bis(diphenylphosphino)propane]palladium(0), palladium(II)acetate, [1,1′-bis(diphenylphosphino)ferrocene]dichloronickel(II) andthe like. Optionally, a base is employed in this reaction, such assodium carbonate, sodium bicarbonate, potassium phosphate, triethylamineand the like. Alternately, compound (1), where R¹ is —SO₂NHR^(1d), mayalso be synthesized as follows:

The starting material, 2-bromobenzene-1-sulfonamide, is commerciallyavailable. Reaction of 2-bromobenzene-1-sulfonamide in a solvent such asDMF, with 1,1-dimethoxy-N,N-dimethylmethanamine, followed by theaddition of sodium hydrogen sulfate in water, yields2-bromo-N-[1-dimethylaminometh-(E)-ylidene]benzenesulfonamide. Thiscompound is reacted with 4-methylphenylboronic acid to yield4′-methylbiphenyl-2-sulfonic acid 1-dimethylaminometh-(E)-ylideneamide,then the —(CH₂)_(r)-L¹ moiety is added, for example, by a halogenationreaction, to form compound (1).

Compound (1) when Ar has one of the remaining formulas can be readilysynthesized using similar techniques or other methods that are wellknown in the art.

Compound (2): This compound is available commercially or can be readilysynthesized by techniques that are well known in the art (Millet et al.(2005) J. Med. Chem. 48:7024-39), such as by reacting a diamine of theformula H₂N—(CH₂)₀₋₁₁—NH₂ and P¹—OC(O)OC(O)O—P¹, for example,(CH₃)₃—COC(O)OC(O)O—C(CH₃)₃ ((BOC)₂O). Examples of compound (2) includeH₂N—(CH₂)₂—NHC(O)O—C(CH₃)₃ (N-(2-aminoethyl) (t-butoxy)carboxamide).

Compound (2′): This compound is available commercially or can be readilysynthesized by techniques that are well known in the art. Examples ofcompound (2′) include H₂N—(CH₂)₂—C(O)O—C(CH₃)₃ (Bachem AG, Switzerland).

Step 2

Compounds (5) and (5′) are prepared by an acylation reaction of compound(3) or (3′) using an appropriate base.

Compound (4): Compound (4) is an acyl halide, examples of which includebutyryl chloride, valeryl chloride, isovaleryl chloride,3-methylpentanoyl chloride, 4-methylpentanoyl chloride, andcyclopropylacetyl chloride. Compound (4) is available commercially orcan be readily synthesized by techniques that are well known in the art,such as by treating the corresponding acid of formula R³—COOH withthionyl chloride or oxalyl chloride.

As noted above, X is C₁₋₁₂alkylene, where at least one —CH₂— moiety inthe alkylene is replaced with a —NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety.Step 3 is performed when a —CH₂— moiety in the alkylene is replaced witha —NR^(4a)—C(O)— moiety. Step 3a is performed when a —CH₂— moiety in thealkylene is replaced with a —C(O)—NR^(4a)— moiety. When only one—CH₂-moiety is replaced, Step 3 or 3a is followed immediately by Step 4or 4a, respectively. When more than one —CH₂— moiety in the alkylene isreplaced, Step 3 or 3a may be followed by as many coupling reactions asis necessary to add the desired amide linkages to the X moiety, beforeproceeding with the next step.

Step 3

Step 3a

Compound (6) is prepared by deprotection of the protected amine, whilecompound (6′) is prepared by deprotection of the protected ester. Anyprotecting groups on the Ar* moiety either remain unaffected from thedeprotection conditions of the P¹ or P² group, or may also bedeprotected in this step. These deprotecting steps can be done in anyorder or simultaneously.

As noted above, when more than one —CH₂— moiety in the alkylene isreplaced, the additional replacements may be made prior to Step 4 or 4a.However, any additional replacements may also be present in compound (7)or (7′) as is depicted in Steps 4 and 4a.

Compound (8) is prepared by coupling of compound (6) and compound (7) orby coupling of compound (6′) and compound (7′) under conventional amidebond-forming conditions.

R⁵* may represent R⁵ as defined herein, or it may represent a protectedform of R⁵. When R⁵* represents R⁵, then the reaction is complete afterthis step, and compound (8) is a compound of formula I. On the otherhand, if R⁵* represents a protected form of R⁵, a subsequentdeprotection step will yield the non-protected compound.

In general, compounds (7) and (7′) can be readily synthesized byfollowing techniques described in the literature, for example, Neustadtet al (1994) J. Med. Chem. 37:2461-2476 and Moree et al. (1995) J. Org.Chem. 60: 5157-69, as well as by using the exemplary proceduresdescribed below. Examples of compound (7) include:

Examples of compound (7′) include:

The synthesis of exemplary compounds (7) and (7′) are described below.In addition, since compounds (7) and (7′) can have a chiral center (notdepicted in the above examples), it may be desirable to synthesize aparticular stereoisomer, and examples are also provided below.

Preparation of Chiral Amino Hydroxamate Compound (7^(i))

A base such as DIPEA and a coupling agent such as EDC are added to asolution of (7a) in DMF containing 1-hydroxybenzotriazole (HOBt) andhydroxylamine hydrochloride. The mixture is stirred at room temperatureuntil completion (approximately 12 hours), then concentrated in vacuo.The resulting material is partitioned and the organic layer collectedand washed with a base (for example, 1M NaOH). The alkaline aqueouslayer is then acidified (for example, with 1M phosphoric acid), andextracted. The organic layer is evaporated and the residue purified bysilica gel chromatography to afford compound (7′) An exemplary compound(7a) is (R)-3-t-butoxycarbonylamino-4-phenylbutyric acid.

Preparation of Sulfanyl Acid Compound (7^(ii))

Compound (7b) is mixed with diethylamine and cooled in an ice bath. Anaqueous formaldehyde solution (37%) is then added, and the mixturestirred at 0° C. for approximately 2 hours, warmed to room temperatureand stirred overnight. The mixture is then extracted with ether, washed,dried, and evaporated to dryness, to provide compound (7c). Compound(7c) is then dissolved in 1,4-dioxane, and a 1M NaOH solution is added.The mixture is stirred at room temperature until completion(approximately 2 days). The organic solvent is removed in vacuo, and theaqueous residue is rinsed with ethyl acetate and acidified toapproximately pH 1 with concentrated HCl. The product is extracted withethyl acetate, dried, and evaporated to dryness to yield compound (7d).Compound (7d) is combined with thiolacetic acid (10 mL), and the mixtureis stirred at 80° C. until completion (approximately 2 hours), thenconcentrated to dryness to yield compound (7^(ii)), which is dissolvedin toluene and concentrated to remove any trace of thiolacetic acid.Examples of compound (7b) include 2-benzylmalonic acid monoethyl ester(R⁶=benzyl) and 2-isobutylmalonic acid monoethyl ester (R⁶=isobutyl).

Preparation of Chiral Amino Sulfhydryl Dimer Compound (7^(iii))

Diisopropyl azodicarboxylate is added to a solution oftriphenylphosphine in a solvent such as THF, cooled in an ice bath. Thesolution is stirred and (7e) and thioacetic acid are added. The mixtureis first stirred at 0° C., then at room temperature until the reactionis complete (approximately 12 hours). The mixture is stripped, dilutedwith ethyl acetate, and washed. The organic layer is dried and thefiltrate evaporated to dryness. The resulting material is flashchromatographed to provide (7f). Compound (7f) is dissolved in asuitable solvent, followed by the addition of a base such as 1M LiOH.Air is bubbled through the solution for 1 hour followed by the additionof solvent. The mixture is stirred at room temperature until thereaction is complete (approximately 24 hours). The solution is thenacidified to approximately pH 5, for example with acetic acid. Theprecipitate is filtered and rinsed, to provide the dimer (7 g). Thissolid is suspended in MeCN, then concentrated in vacuo. The recoveredmaterial is dissolved in 4M HCl in 1,4-dioxane and stirred at roomtemperature until the reaction is complete (approximately 2 hours). Themixture is then concentrated under reduced pressure, and triturated withethyl acetate. The product is filtered, washed, and dried in vacuo toprovide compound (7^(iii)). An exemplary compound (7e) is((R)-1-benzyl-(2-hydroxyethyl)carbamic acid t-butyl ester.

Preparation of Chiral Sulfanyl Acid Compound (7^(iv))

Compound (7h) is formed by dissolving a compound such as D-leucine (forR⁶=isobutyl) in 3M HBr (aqueous) and cooled to 0° C. A solution ofsodium nitrite in water is added, and the mixture is stirred at 0° C.until the reaction is complete (approximately 2.5 hours). The mixture isthen extracted with ethyl acetate, washed, dried, filtered, andconcentrated to afford (7h). Compound (7h) is combined with potassiumthioacetate and DMF, and the mixture stirred at room temperature untilthe reaction is complete (approximately 1 hour). Water is added, and themixture is extracted, washed, dried, filtered, and concentrated toprovide compound (7^(iv)). The product is purified by silica gelchromatography. An exemplary compound (7h) is(R)-2-bromo-4-methylpentanoic acid.

Preparation of Chiral Sulfanyl Acid Compound (7^(v))

Compound (7i), (S)-4-benzyl-2-oxazolidinone, is commercially available.Compound (7j) is also typically commercially available or can be readilysynthesized. For example, R⁶—CH₂—COOH (for example, isocaproic acid or3-phenylpropionic acid) is dissolved in methylene chloride and thionylchloride is added. The mixture is stirred at room temperature until thereaction is complete (for example, overnight), and then concentrated toprovide (7j). Examples of compound (7j) include 4-methylpentanoylchloride and 3-phenylpropionyl chloride.

Compound (7i) is dissolved in a suitable solvent and cooled (−78° C.)under nitrogen. n-Butyllithium in hexanes is added dropwise and stirred,followed by the addition of (7j) dropwise. The mixture is stirred at−78° C., then warmed to 0° C. Saturated NaHCO₃ is added and the mixturewarmed to room temperature. The mixture is extracted, washed, dried,filtered, and concentrated to afford (7k). Compound (7k) is dissolved inDCM and stirred at 0° C. under nitrogen. 1M Titanium tetrachloride isadded, followed by 1,3,5-trioxane, all in appropriate solvents. A secondequivalent of 1M titanium tetrachloride is added and the mixture stirredat 0° C. until the reaction is complete. The mixture is then quenchedwith saturated ammonium chloride. Appropriate solvents are added, theaqueous phase is extracted, and the organic layers are combined, dried,filtered, and concentrated to provide (7l), which can then be purifiedby silica gel chromatography or used in the next step without furtherpurification. Compound (7l) is dissolved in a solvent, to which is added9 M hydrogen peroxide in water, followed by the dropwise addition of 1.5M lithium hydroxide monohydrate in water. The mixture is warmed to roomtemperature and stirred. Optionally, potassium hydroxide may be addedand the mixture heated at 60° C. then cooled at room temperature. Tothis is added an aqueous solution of sodium sulfite followed by waterand chloroform. The aqueous layer is extracted, acidified and extractedagain. The organic layer is washed, dried, filtered, and rotovaped toprovide (7m). Triphenylphosphine is dissolved in an appropriate solventand cooled at 0° C. (ice bath). Diisopropyl azodicarboxylate is addeddropwise and the mixture stirred. Compound (7m) and thioacetic acid,dissolved in an appropriate solvent, are added dropwise to the mixture.After the addition, the mixture is removed from the ice bath and stirredat room temperature until the reaction is complete (approximately 3.5hours), concentrated, and then partitioned. The organic layer isextracted and the combined aqueous extracts washed, acidified andextracted. The organic layer is washed again, dried, filtered, androtovaped to provide compound (7^(v)).

Alternately, the coupling step can be done by the two-step method shownbelow:

The coupling reaction can be done, for example, in the presence of ahalogen-substituted alkanoic acid (“L-acid”) such as α-bromoisocaproicacid to provide compound (9), where L is a leaving group such as bromo.Compound (9) is then reacted with a thiol or sulfur-containingnucleophilic reactant that contains the desired R⁵* group, for example,potassium thioacetate or thiourea.

Step 5 Optional

The reaction is complete after Step 4 when R⁵* represents R⁵ in compound(8) and R¹ does not contain any protecting groups. However, when R⁵*represents a protected form of R⁵ and R¹ is a protected form, a globalor sequential deprotection step of compound (8) will provide the desiredcompound. Reagents and conditions for the deprotection vary with thenature of protecting groups in the compound (8). Typical deprotectionconditions when R⁵* represents C₀₋₃alkylene-S—P³, include treating thecompound with NaOH in an alcoholic solvent at room temperature to yieldthe non-protected compound. Typical deprotection conditions when R¹*represents C(O)O—P² where P² refers to t-butyl include treating thecompound with TFA in DCM at room temperature to yield the non-protectedcompound.

In an alternate synthesis, compound (3) is reacted with a protectingreagent (P¹′-L) such as Cbz-Cl to provide compound (10), where L is aleaving group such as chloro and P¹′ is a different amino-protectinggroup than P¹:

Compound (10) is then selectively deprotected to yield compound (11),which is then coupled with compound (7) to provide compound (12).

Compound (12) is then selectively deprotected to yield compound (13),which is then acylated with compound (4) to yield compound (8).

The following synthesis is useful, for example, when a carbon atom inthe alkylene moiety in X is substituted with an R^(4b) group:

A standard alkylation reaction between compounds (1) and (14) providescompound (15), which is then acylated using compound (4) to provide(16). Examples of compound (14) include (2S)-2-aminopropan-1-ol.

Compound (16) then undergoes an oxidation reaction of the alcohol toform the aldehyde (17), which is then converted to the oxime (18) byreaction with hydroxylamine hydrochloride.

Compound (18) is then reduced to the amine (19), which is then coupledwith compound (7) and deprotected, if needed, to provide (8′), where Xis substituted an R^(4b) group.

If desired, pharmaceutically acceptable salts of the compounds offormula I can be prepared by contacting the free acid or base form of acompound of formula I with a pharmaceutically acceptable base or acid.

Certain of the intermediates described herein are believed to be noveland accordingly, such compounds are provided as further aspects of theinvention including, for example, the compounds of formulas II, II andIV, and salts thereof:

where Ar* is Ar—R¹*; Ar, r, R³, X, and R⁵⁻⁷ are as defined for formulaI; and R¹* is selected from —C(O)O—P², —SO₂O—P⁵, —SO₂NH—P⁶,—P(O)(O—P⁷)₂, —OCH(CH₃)—C(O)O—P², —OCH(aryl)-C(O)O—P², andtetrazol-5-yl-P⁴; where P² is a carboxy-protecting group, P⁴ is atetrazole-protecting group, P⁵ is a hydroxyl-protecting group, P⁶ is asulfonamide-protecting group, and P⁷ is a phosphonate-protecting groupor phosphinate-protecting group;

where Ar, r, R³, X, and R⁶⁻⁷ are as defined for formula I; R⁵* isselected from —C₀₋₃alkylene-S—P³, —C₀₋₃alkylene-C(O)NH(O—P⁵),—C₀₋₃alkylene-N(O—P⁵)—C(O)R^(1d), —C₀₋₁alkylene-NHC(O)CH₂S—P³,—NH—C₀₋₁alkylene-P(O)(O—P⁷)₂, —C₀₋₃alkylene-P(O)(O—P⁷)—R^(5f),—C₀₋₂alkylene-CHR^(5g)—C(O)O—P² and—C₀₋₃alkylene-C(O)NR^(5h)—CHR^(5i)—C(O)O—P²; and R^(5d) to R^(5i) are asdefined for formula I; where P² is a carboxy-protecting group, P³ is athiol-protecting group, P⁵ is a hydroxyl-protecting group, and P⁷ is aphosphonate-protecting group or phosphinate-protecting group; and

Where Ar* is Ar—R¹*; Ar, r, R³, X, and R⁶⁻⁷ are as defined for formulaI; R¹* is selected from —C(O)O—P², —SO₂O—P⁵, —SO₂NH—P⁶, —P(O)(O—P⁷)₂,—OCH(CH₃)—C(O)O—P², —OCH(aryl)-C(O)O—P², and tetrazol-5-yl-P⁴; R⁵* isselected from —C₀₋₃alkylene-S—P³, —C₀₋₃alkylene-C(O)NH(O—P⁵),—C₀₋₃alkylene-N(O—P⁵)—C(O)R^(5d), —C₀₋₁alkylene-NHC(O)CH₂S—P³,—NH—C₀₋₁alkylene-P(O)(O—P⁷)₂, —C₀₋₃alkylene-P(O)(O—P⁷)—R^(5f),—C₀₋₂alkylene-CHR^(5g)—C(O)O—P² and—C₀₋₃alkylene-C(O)NR^(5h)—CHR^(5i)—C(O)O—P²; and R^(5d) to R^(5i) are asdefined for formula I; where P² is a carboxy-protecting group, P³ is athiol-protecting group, P⁴ is a tetrazole-protecting group, P⁵ is ahydroxyl-protecting group, P⁶ is a sulfonamide-protecting group, and P⁷is a phosphonate-protecting group or phosphinate-protecting group. Thus,another method of preparing compounds of the invention involvesdeprotecting a compound of formula II, III, or IV.

Further details regarding specific reaction conditions and otherprocedures for preparing representative compounds of the invention orintermediates thereof are described in the Examples set forth below.

Utility

Compounds of the invention possess angiotensin II type 1 (AT₁) receptorantagonist activity. In one embodiment, compounds of the invention areselective for inhibition of the AT₁ receptor over the AT₂ receptor.Compounds of the invention also possess neprilysin (NEP) inhibitionactivity, that is, the compounds are able to inhibit enzyme-substrateactivity. In another embodiment, the compounds do not exhibitsignificant inhibitory activity of the angiotensin-converting enzyme.Compounds of formula I may be active drugs as well as prodrugs. Thus,when discussing the activity of compounds of the invention, it isunderstood that any such prodrugs have the expected AT₁ and NEP activityonce metabolized.

One measure of a compound's affinity for the AT₁ receptor is theinhibitory constant (K_(i)) for binding to the AT₁ receptor. The pK_(i)value is the negative logarithm to base 10 of the K_(i). One measure ofthe ability of a compound to inhibit NEP activity is the inhibitoryconcentration (IC₅₀), which is the concentration of compound thatresults in half-maximal inhibition of substrate conversion by the NEPenzyme. The pIC₅₀ value is the negative logarithm to base 10 of theIC₅₀. Compounds of formula I and pharmaceutically acceptable saltsthereof that have both AT₁ receptor-antagonizing activity and NEPenzyme-inhibiting activity are of particular interest, including thosethat exhibit a pK_(i) at the AT₁ receptor greater than or equal to about5.0, and having a pIC₅₀ for NEP greater than or equal to about 5.0.

In one embodiment, compounds of interest have a pK_(i) at the AT₁receptor≧about 6.0, a pK_(i) at the AT₁ receptor≧about 7.0, or a pK_(i)at the AT₁ receptor≧about 8.0. Compounds of interest also include thosehaving a pIC₅₀ for NEP≧about 6.0 or a pIC₅₀ for NEP≧about 7.0. Inanother embodiment, compounds of interest have a pK_(i) at the AT₁receptor within the range of about 8.0-10.0 and a pIC₅₀ for NEP withinthe range of about 7.0-10.0.

In one embodiment, compounds of interest have a pK_(i) for binding to anAT₁ receptor greater than or equal to about 7.5 and a NEP enzyme pIC₅₀greater than or equal to about 7.0. In another embodiment, compounds ofinterest have a pK_(i) greater than or equal to about 8.0 and a pIC₅₀greater than or equal to about 8.0.

It is noted that in some cases, compounds of the invention, while stillhaving dual activity, may possess either weak AT₁ receptor antagonistactivity or weak NEP inhibition activity. In such cases, those of skillin the art will recognize that these compounds still have utility asprimarily either a NEP inhibitor or a AT₁ receptor antagonist,respectively, or have utility as research tools.

Exemplary assays to determine properties of compounds of the invention,such as the AT₁ receptor binding and/or NEP inhibiting activity, aredescribed in the Examples and include by way of illustration and notlimitation, assays that measure AT₁ and AT₂ binding (described in Assay1), and NEP inhibition (described in Assay 2). Useful secondary assaysinclude assays to measure ACE inhibition (also described in Assay 2) andaminopeptidase P (APP) inhibition (described in Sulpizio et al. (2005)JPET 315:1306-1313). A pharmacodynamic assay to assess the in vivoinhibitory potencies for ACE, AT₁, and NEP in anesthetized rats isdescribed in Assay 3 (see also Seymour et al. Hypertension 7(SupplI):I-35-I-42, 1985 and Wigle et al. Can. J. Physiol. Pharmacol.70:1525-1528, 1992), where AT₁ inhibition is measured as the percentinhibition of the angiotensin II pressor response, ACE inhibition ismeasured as the percent inhibition of the angiotensin I pressorresponse, and NEP inhibition is measured as increased urinary cyclicguanosine 3′,5′-monophosphate (cGMP) output. Useful in vivo assaysinclude the conscious spontaneously hypertensive rat (SHR) model, whichis a renin dependent hypertension model useful for measuring AT₁receptor blocking (described in Assay 4; see also Intengan et al. (1999)Circulation 100(22):2267-2275 and Badyal et al. (2003) Indian Journal ofPharmacology 35:349-362), and the conscious desoxycorticosteroneacetate-salt (DOCA-salt) rat model, which is a volume dependenthypertension model useful for measuring NEP activity (described in Assay5; see also Trapani et al. (1989) J. Cardiovasc. Pharmacol. 14:419-424,Intengan et al. (1999) Hypertension 34(4):907-913, and Badyal et al.(2003) supra). Both the SHR and DOCA-salt models are useful forevaluating the ability of a test compound to reduce blood pressure. TheDOCA-salt model is also useful to measure a test compound's ability toprevent or delay a rise in blood pressure. Compounds of the inventionare expected to antagonize the AT₁ receptor and/or inhibit the NEPenzyme in any of the assays listed above, or assays of a similar nature.Thus, the aforementioned assays are useful in determining thetherapeutic utility of compounds of the invention, for example, theirutility as antihypertensive agents. Other properties and utilities ofcompounds of the invention can be demonstrated using other in vitro andin vivo assays well known to those skilled in the art.

Compounds of the invention are expected to be useful for the treatmentand/or prevention of medical conditions responsive to AT₁ receptorantagonism and/or NEP inhibition. Thus it is expected that patientssuffering from a disease or disorder that is treated by antagonizing theAT₁ receptor and/or by inhibiting the NEP enzyme can be treated byadministering a therapeutically effective amount of a compound of theinvention. For example, by antagonizing the AT₁ receptor and thusinterfering with the action of angiotensin II on its receptors, thesecompounds are expected to find utility in preventing the increase inblood pressure produced by angiotensin II, a potent vasopressor. Inaddition, by inhibiting NEP, these compounds are also expected topotentiate the biological effects of endogenous peptides that aremetabolized by NEP, such as the natriuretic peptides, bombesin,bradykinins, calcitonin, endothelins, enkephalins, neurotensin,substance P and vasoactive intestinal peptide. For example, bypotentiating the effects of the natriuretic peptides, compounds of theinvention are expected to be useful to treat glaucoma. These compoundsare also expected to have other physiological actions, for example, onthe renal, central nervous, reproductive and gastrointestinal systems.

Compounds of the invention are expected to find utility in treatingand/or preventing medical conditions such as cardiovascular and renaldiseases. Cardiovascular diseases of particular interest include heartfailure such as congestive heart failure, acute heart failure, chronicheart failure, and acute and chronic decompensated heart failure. Renaldiseases of particular interest include diabetic nephropathy and chronickidney disease. One embodiment of the invention is directed to a methodfor treating hypertension, comprising administering to a patient atherapeutically effective amount of a compound of the invention.Typically, the therapeutically effective amount is the amount that issufficient to lower the patient's blood pressure. In one embodiment, thecompound is administered as an oral dosage form.

Another embodiment of the invention is directed to a method for treatingheart failure, comprising administering to a patient a therapeuticallyeffective amount of a compound of the invention. Typically, thetherapeutically effective amount is the amount that is sufficient tolower blood pressure and/or improve renal functions. In one embodiment,the compound is administered as an intravenous dosage form. When used totreat heart failure, the compound may be administered in combinationwith other therapeutic agents such as diuretics, natriuretic peptides,and adenosine receptors antagonist.

Compounds of the invention are also expected to be useful inpreventative therapy, for example in preventing the progression ofcardiac insufficiency after myocardial infarction, preventing arterialrestenosis after angioplasty, preventing thickening of blood vesselwalls after vascular operations, preventing atherosclerosis, andpreventing diabetic angiopathy.

In addition, as NEP inhibitors, compounds of the invention are expectedto inhibit enkephalinase, which will inhibit the degradation ofendogenous enkephalins. Thus, such compounds may also find utility asanalgesics. Due to their NEP inhibition properties, compounds of theinvention are also expected to be useful as antitussive agents andantidiarrheal agents (for example, for the treatment of waterydiarrhea), as well as find utility in the treatment of menstrualdisorders, preterm labor, pre-eclampsia, endometriosis, reproductivedisorders (for example, male and female infertility, polycystic ovariansyndrome, implantation failure), and male and female sexual dysfunction,including male erectile dysfunction and female sexual arousal disorder.More specifically, the compounds of the invention are expected to beuseful in treating female sexual dysfunction, which is often defined asa female patient's difficulty or inability to find satisfaction insexual expression. This covers a variety of diverse female sexualdisorders including, by way of illustration and not limitation,hypoactive sexual desire disorder, sexual arousal disorder, orgasmicdisorder and sexual pain disorder. When used to treat such disorders,especially female sexual dysfunction, compounds of the invention may becombined with one or more of the following secondary agents: PDE5inhibitors, dopamine agonists, estrogen receptor agonists and/orantagonists, androgens, and estrogens.

The amount of the compound of the invention administered per dose or thetotal amount administered per day may be predetermined or it may bedetermined on an individual patient basis by taking into considerationnumerous factors, including the nature and severity of the patient'scondition, the condition being treated, the age, weight, and generalhealth of the patient, the tolerance of the patient to the compound, theroute of administration, pharmacological considerations such as theactivity, efficacy, pharmacokinetics and toxicology profiles of thecompound and any secondary agents being administered, and the like.Treatment of a patient suffering from a disease or medical condition(such as hypertension) can begin with a predetermined dosage or a dosagedetermined by the treating physician, and then continue for the periodof time necessary to prevent, ameliorate, suppress, or alleviate thesymptoms of the disease or medical condition. Patients undergoing suchtreatment will typically be monitored on a routine basis to determinethe effectiveness of therapy. For example, in treating hypertension,blood pressure measurements may be used to determine the effectivenessof treatment. Similar indicators for the other diseases and conditionsdescribed herein, are well known and are readily available to thetreating physician. Continuous monitoring by the physician will insurethat the optimal amount of the compound of the invention will beadministered at any given time, as well as facilitating thedetermination of the duration of treatment. This is of particular valuewhen secondary agents are also being administered, as their selection,dosage, and duration of therapy may also require adjustment. In thisway, the treatment regimen and dosing schedule can be adjusted over thecourse of therapy so that the lowest amount of compound that exhibitsthe desired effectiveness is administered and, further, thatadministration is continued only so long as is necessary to successfullytreat the disease or medical condition.

Since compounds of the invention possess AT₁ receptor antagonistactivity and/or NEP enzyme inhibition activity, these compounds are alsouseful as research tools for investigating or studying biologicalsystems or samples having AT₁ receptors or a NEP enzyme, for example tostudy diseases where the AT₁ receptor or NEP enzyme plays a role. Anysuitable biological system or sample having AT₁ receptors and/or a NEPenzyme may be employed in such studies which may be conducted either invitro or in vivo. Representative biological systems or samples suitablefor such studies include, but are not limited to, cells, cellularextracts, plasma membranes, tissue samples, isolated organs, mammals(such as mice, rats, guinea pigs, rabbits, dogs, pigs, humans, and soforth), and the like, with mammals being of particular interest. In oneparticular embodiment of the invention an AT₁ receptor in a mammal isantagonized by administering an AT₁-antagonizing amount of a compound ofthe invention. In another particular embodiment, NEP enzyme activity ina mammal is inhibited by administering a NEP-inhibiting amount of acompound of the invention. Compounds of the invention can also be usedas research tools by conducting biological assays using these compounds.

When used as a research tool, a biological system or sample comprisingan AT₁ receptor and/or a NEP enzyme is typically contacted with an AT₁receptor-antagonizing or NEP enzyme-inhibiting amount of a compound ofthe invention. After the biological system or sample is exposed to thecompound, the effects of antagonizing the AT₁ receptor and/or inhibitingthe NEP enzyme are determined using conventional procedures andequipment, such as by measuring receptor binding in a binding assay ormeasuring ligand-mediated changes in a functional assay. Exposureencompasses contacting cells or tissue with the compound, administeringthe compound to a mammal, for example by i.p., i.v. or s.c.administration, and so forth. The determining step can involve measuringa response (a quantitative analysis) or can involve making anobservation (a qualitative analysis). Measuring a response involves, forexample, determining the effects of the compound on the biologicalsystem or sample using conventional procedures and equipment, such asradioligand binding assays or measuring ligand-mediated changes infunctional assays. The assay results can be used to determine theactivity level as well as the amount of compound necessary to achievethe desired result, such as an AT₁ receptor-antagonizing and/or a NEPenzyme-inhibiting amount. Typically, the determining step will involvedetermining the AT₁ receptor ligand-mediated effects and/or determiningthe effects of inhibiting the NEP enzyme.

Additionally, compounds of the invention can be used as research toolsfor evaluating other chemical compounds, and thus are also useful inscreening assays to discover, for example, new compounds having AT₁receptor-antagonizing activity and/or NEP-inhibiting activity. In thismanner, a compound of the invention is used as a standard in an assay toallow comparison of the results obtained with a test compound and withcompounds of the invention to identify those test compounds that haveabout equal or superior activity, if any. For example, K_(i) data (asdetermined, for example, by a binding assay) for a test compound or agroup of test compounds is compared to the K_(i) data for a compound ofthe invention to identify those test compounds that have the desiredproperties, for example, test compounds having a K_(i) value about equalor superior to a compound of the invention, if any. This aspect of theinvention includes, as separate embodiments, both the generation ofcomparison data (using the appropriate assays) and the analysis of testdata to identify test compounds of interest. Thus, a test compound canbe evaluated in a biological assay, by a method comprising the steps of:(a) conducting a biological assay with a test compound to provide afirst assay value; (b) conducting the biological assay with a compoundof the invention to provide a second assay value; wherein step (a) isconducted either before, after or concurrently with step (b); and (c)comparing the first assay value from step (a) with the second assayvalue from step (b). Exemplary biological assays include AT₁ receptorbinding assays and NEP enzyme inhibition assays.

Pharmaceutical Compositions and Formulations

Compounds of the invention are typically administered to a patient inthe form of a pharmaceutical composition or formulation. Suchpharmaceutical compositions may be administered to the patient by anyacceptable route of administration including, but not limited to, oral,rectal, vaginal, nasal, inhaled, topical (including transdermal),ocular, and parenteral modes of administration. Further, the compoundsof the invention may be administered, for example orally, in multipledoses per day (for example, two, three, or four times daily), in asingle daily dose or a single weekly dose. It will be understood thatany form of the compounds of the invention, (free base, free acid,pharmaceutically acceptable salt, solvate, etc.) that is suitable forthe particular mode of administration can be used in the pharmaceuticalcompositions discussed herein.

Accordingly, in one embodiment, the invention is directed to apharmaceutical composition comprising a pharmaceutically acceptablecarrier and a compound of the invention. The compositions may containother therapeutic and/or formulating agents if desired. When discussingcompositions, the “compound of the invention” may also be referred toherein as the “active agent,” to distinguish it from other components ofthe formulation, such as the carrier. Thus, it is understood that theterm “active agent” includes compounds of formula I as well aspharmaceutically acceptable salts, solvates and prodrugs of thatcompound.

The pharmaceutical compositions of the invention typically contain atherapeutically effective amount of a compound of the invention. Thoseskilled in the art will recognize, however, that a pharmaceuticalcomposition may contain more than a therapeutically effective amount,such as in bulk compositions, or less than a therapeutically effectiveamount, such as in individual unit doses designed for multipleadministration to achieve a therapeutically effective amount. Typically,the composition will contain from about 0.01-95 wt % of active agent,including, from about 0.01-30 wt %, such as from about 0.01-10 wt %,with the actual amount depending upon the formulation itself, the routeof administration, the frequency of dosing, and so forth. In oneembodiment, a composition suitable for an oral dosage form, for example,may contain about 5-70 wt %, or from about 10-60 wt % of active agent.

Any conventional carrier or excipient may be used in the pharmaceuticalcompositions of the invention. The choice of a particular carrier orexcipient, or combinations of carriers or excipients, will depend on themode of administration being used to treat a particular patient or typeof medical condition or disease state. In this regard, the preparationof a suitable composition for a particular mode of administration iswell within the scope of those skilled in the pharmaceutical arts.Additionally, carriers or excipients used in such compositions arecommercially available. By way of further illustration, conventionalformulation techniques are described in Remington: The Science andPractice of Pharmacy, 20th Edition, Lippincott Williams & White,Baltimore, Md. (2000); and H. C. Ansel et al., Pharmaceutical DosageForms and Drug Delivery Systems, 7^(th) Edition, Lippincott Williams &White, Baltimore, Md. (1999).

Representative examples of materials which can serve as pharmaceuticallyacceptable carriers include, but are not limited to, the following:sugars, such as lactose, glucose and sucrose; starches, such as cornstarch and potato starch; cellulose, such as microcrystalline cellulose,and its derivatives, such as sodium carboxymethyl cellulose, ethylcellulose and cellulose acetate; powdered tragacanth; malt; gelatin;talc; excipients, such as cocoa butter and suppository waxes; oils, suchas peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil,corn oil and soybean oil; glycols, such as propylene glycol; polyols,such as glycerin, sorbitol, mannitol and polyethylene glycol; esters,such as ethyl oleate and ethyl laurate; agar; buffering agents, such asmagnesium hydroxide and aluminum hydroxide; alginic acid; pyrogen-freewater; isotonic saline; Ringer's solution; ethyl alcohol; phosphatebuffer solutions; compressed propellant gases, such aschlorofluorocarbons and hydrofluorocarbons; and other non-toxiccompatible substances employed in pharmaceutical compositions.

Pharmaceutical compositions are typically prepared by thoroughly andintimately mixing or blending the active agent with a pharmaceuticallyacceptable carrier and one or more optional ingredients. The resultinguniformly blended mixture may then be shaped or loaded into tablets,capsules, pills, canisters, cartridges, dispensers and the like usingconventional procedures and equipment.

In formulations where the compound of the invention contains a thiolgroup, additional consideration may be given to minimize or eliminateoxidation of the thiol to form a disulfide. In solid formulations, thismay be accomplished by reducing the drying time, decreasing the moisturecontent of the formulation, and including materials such as ascorbicacid, sodium ascorbate, sodium sulfite and sodium bisulfite, as well asmaterials such as a mixture of lactose and microcrystalline cellulose.In liquid formulations, stability of the thiol may be improved by theaddition of amino acids, antioxidants, or a combination of disodiumedetate and ascorbic acid.

In one embodiment, the pharmaceutical compositions are suitable for oraladministration. Suitable compositions for oral administration may be inthe form of capsules, tablets, pills, lozenges, cachets, dragees,powders, granules; solutions or suspensions in an aqueous or non-aqueousliquid; oil-in-water or water-in-oil liquid emulsions; elixirs orsyrups; and the like; each containing a predetermined amount of theactive agent.

When intended for oral administration in a solid dosage form (capsules,tablets, pills and the like), the composition will typically comprisethe active agent and one or more pharmaceutically acceptable carriers,such as sodium citrate or dicalcium phosphate. Solid dosage forms mayalso comprise: fillers or extenders, such as starches, microcrystallinecellulose, lactose, sucrose, glucose, mannitol, and/or silicic acid;binders, such as carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidone, sucrose and/or acacia; humectants, such as glycerol;disintegrating agents, such as agar-agar, calcium carbonate, potato ortapioca starch, alginic acid, certain silicates, and/or sodiumcarbonate; solution retarding agents, such as paraffin; absorptionaccelerators, such as quaternary ammonium compounds; wetting agents,such as cetyl alcohol and/or glycerol monostearate; absorbents, such askaolin and/or bentonite clay; lubricants, such as talc, calciumstearate, magnesium stearate, solid polyethylene glycols, sodium laurylsulfate, and/or mixtures thereof; coloring agents; and buffering agents.

Release agents, wetting agents, coating agents, sweetening, flavoringand perfuming agents, preservatives and antioxidants may also be presentin the pharmaceutical compositions. Exemplary coating agents fortablets, capsules, pills and like, include those used for entericcoatings, such as cellulose acetate phthalate, polyvinyl acetatephthalate, hydroxypropyl methylcellulose phthalate, methacrylicacid-methacrylic acid ester copolymers, cellulose acetate trimellitate,carboxymethyl ethyl cellulose, hydroxypropyl methyl cellulose acetatesuccinate, and the like. Examples of pharmaceutically acceptableantioxidants include: water-soluble antioxidants, such as ascorbic acid,cysteine hydrochloride, sodium bisulfate, sodium metabisulfate sodiumsulfite and the like; oil-soluble antioxidants, such as ascorbylpalmitate, butylated hydroxyanisole, butylated hydroxytoluene, lecithin,propyl gallate, alpha-tocopherol, and the like; and metal-chelatingagents, such as citric acid, ethylenediamine tetraacetic acid, sorbitol,tartaric acid, phosphoric acid, and the like.

Compositions may also be formulated to provide slow or controlledrelease of the active agent using, by way of example, hydroxypropylmethyl cellulose in varying proportions or other polymer matrices,liposomes and/or microspheres. In addition, the pharmaceuticalcompositions of the invention may contain opacifying agents and may beformulated so that they release the active agent only, orpreferentially, in a certain portion of the gastrointestinal tract,optionally, in a delayed manner. Examples of embedding compositionswhich can be used include polymeric substances and waxes. The activeagent can also be in micro-encapsulated form, optionally with one ormore of the above-described excipients.

Suitable liquid dosage forms for oral administration include, by way ofillustration, pharmaceutically acceptable emulsions, microemulsions,solutions, suspensions, syrups and elixirs. Liquid dosage formstypically comprise the active agent and an inert diluent, such as, forexample, water or other solvents, solubilizing agents and emulsifiers,such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethylacetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butyleneglycol, oils (for example, cottonseed, groundnut, corn, germ, olive,castor and sesame oils), glycerol, tetrahydrofuryl alcohol, polyethyleneglycols and fatty acid esters of sorbitan, and mixtures thereof.Suspensions may contain suspending agents such as, for example,ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitanesters, microcrystalline cellulose, aluminium metahydroxide, bentonite,agar-agar and tragacanth, and mixtures thereof.

When intended for oral administration, the pharmaceutical compositionsof the invention may be packaged in a unit dosage form. The term “unitdosage form” refers to a physically discrete unit suitable for dosing apatient such that each unit contains a predetermined quantity of theactive agent calculated to produce the desired therapeutic effect eitheralone or in combination with one or more additional units. For example,such unit dosage forms may be capsules, tablets, pills, and the like.

In another embodiment, the compositions of the invention are suitablefor inhaled administration, and will typically be in the form of anaerosol or a powder. Such compositions are generally administered usingwell known delivery devices, such as a nebulizer, dry powder, ormetered-dose inhaler. Nebulizer devices produce a stream of highvelocity air that causes the composition to spray as a mist that iscarried into a patient's respiratory tract. An exemplary nebulizerformulation comprises the active agent dissolved in a carrier to form asolution, or micronized and combined with a carrier to form a suspensionof micronized particles of respirable size. Dry powder inhalersadminister the active agent as a free-flowing powder that is dispersedin a patient's air-stream during inspiration. An exemplary dry powderformulation comprises the active agent dry-blended with an excipientsuch as lactose, starch, mannitol, dextrose, polylactic acid,polylactide-co-glycolide, and combinations thereof. Metered-doseinhalers discharge a measured amount of the active agent usingcompressed propellant gas. An exemplary metered-dose formulationcomprises a solution or suspension of the active agent in a liquefiedpropellant, such as a chlorofluorocarbon or hydrofluoroalkane. Optionalcomponents of such formulations include co-solvents, such as ethanol orpentane, and surfactants, such as sorbitan trioleate, oleic acid,lecithin, glycerin, and sodium lauryl sulfate. Such compositions aretypically prepared by adding chilled or pressurized hydrofluoroalkane toa suitable container containing the active agent, ethanol (if present)and the surfactant (if present). To prepare a suspension, the activeagent is micronized and then combined with the propellant.Alternatively, a suspension formulation can be prepared by spray dryinga coating of surfactant on micronized particles of the active agent. Theformulation is then loaded into an aerosol canister, which forms aportion of the inhaler.

Compounds of the invention can also be administered parenterally (forexample, by subcutaneous, intravenous, intramuscular, or intraperitonealinjection). For such administration, the active agent is provided in asterile solution, suspension, or emulsion. Exemplary solvents forpreparing such formulations include water, saline, low molecular weightalcohols such as propylene glycol, polyethylene glycol, oils, gelatin,fatty acid esters such as ethyl oleate, and the like. Parenteralformulations may also contain one or more anti-oxidants, solubilizers,stabilizers, preservatives, wetting agents, emulsifiers, and dispersingagents. Surfactants, additional stabilizing agents or pH-adjustingagents (acids, bases or buffers) and anti-oxidants are particularlyuseful to provide stability to the formulation, for example, to minimizeor avoid hydrolysis of ester and amide linkages, or dimerization ofthiols that may be present in the compound. These formulations may berendered sterile by use of a sterile injectable medium, a sterilizingagent, filtration, irradiation, or heat.

Compounds of the invention can also be administered transdermally usingknown transdermal delivery systems and excipients. For example, thecompound can be admixed with permeation enhancers, such as propyleneglycol, polyethylene glycol monolaurate, azacycloalkan-2-ones and thelike, and incorporated into a patch or similar delivery system.Additional excipients including gelling agents, emulsifiers and buffers,may be used in such transdermal compositions if desired.

If desired, the compounds of the invention may be administered incombination with one or more other therapeutic agents. Thus, in oneembodiment, pharmaceutical compositions of the invention contain otherdrugs that are co-administered with the compound of the invention. Forexample, the composition may further comprise one or more drugs, alsoreferred to as “secondary agents(s)”, selected from the group ofdiuretics, β₁ adrenergic receptor blockers, calcium channel blockers,angiotensin-converting enzyme inhibitors, AT₁ receptor antagonists,neprilysin inhibitors, non-steroidal anti-inflammatory agents,prostaglandins, anti-lipid agents, anti-diabetic agents, anti-thromboticagents, renin inhibitors, endothelin receptor antagonists, endothelinconverting enzyme inhibitors, aldosterone antagonists,angiotensin-converting enzyme/neprilysin inhibitors, and combinationsthereof. Such therapeutic agents are well known in the art, and examplesare described below. By combining a compound of the invention with asecondary agent, triple therapy can be achieved; AT₁ receptor antagonistactivity, NEP inhibition activity and activity associated with thesecondary agent (for example, β₁ adrenergic receptor blocker) can beachieved using only two active components. Since compositions containingtwo active components are typically easier to formulate thancompositions containing three active components, such two-componentcompositions provide a significant advantage over compositionscontaining three active components. Accordingly, in yet another aspectof the invention, a pharmaceutical composition comprises a compound ofthe invention, a second active agent, and a pharmaceutically acceptablecarrier. Third, fourth, etc. active agents may also be included in thecomposition. In combination therapy, the amount of the compound of theinvention that is administered, as well as the amount of secondaryagents, may be less than the amount typically administered inmonotherapy.

Compounds of the invention may be either physically mixed with thesecond active agent to form a composition containing both agents; oreach agent may be present in separate and distinct compositions whichare administered to the patient simultaneously or at separate times. Forexample, compounds of the invention can be combined with a second activeagent using conventional procedures and equipment to form a combinationof active agents comprising a compound of the invention and a secondactive agent. Additionally, the active agents may be combined with apharmaceutically acceptable carrier to form a pharmaceutical compositioncomprising a compound of the invention, a second active agent and apharmaceutically acceptable carrier. In this embodiment, the componentsof the composition are typically mixed or blended to create a physicalmixture. The physical mixture is then administered in a therapeuticallyeffective amount using any of the routes described herein.

Alternatively, the active agents may remain separate and distinct beforeadministration to the patient. In this embodiment, the agents are notphysically mixed together before administration but are administeredsimultaneously or at separate times as separate compositions. Suchcompositions can be packaged separately or may be packaged together in akit. When administered at separate times, the secondary agent willtypically be administered less than 24 hours after administration of acompound of the invention, ranging anywhere from concurrent withadministration of a compound of the invention to about 24 hourspost-dose. This is also referred to as sequential administration. Thus,compounds of the invention can be orally administered simultaneously orsequentially with another active agent using two tablets, with onetablet for each active agent, where sequential may mean beingadministered immediately after administration of the compound of theinvention or at some predetermined time later (for example, one hourlater or three hours later). Alternatively, the combination may beadministered by different routes of administration, for example, oneorally and the other by inhalation.

In one embodiment, the kit comprises a first dosage form comprising acompound of the invention and at least one additional dosage formcomprising one or more of the secondary agents set forth herein, inquantities sufficient to carry out the methods of the invention. Thefirst dosage form and the second (or third, etc,) dosage form togethercomprise a therapeutically effective amount of active agents for thetreatment or prevention of a disease or medical condition in a patient.

Secondary agent(s), when included, are present in a therapeuticallyeffective amount such that they are typically administered in an amountthat produces a therapeutically beneficial effect when co-administeredwith a compound of the invention. The secondary agent can be in the formof a pharmaceutically acceptable salt, solvate, optically purestereoisomer, and so forth. The secondary agent may also be in the formof a prodrug, for example, a compound having a carboxylic acid groupthat has been esterified. Thus, secondary agents listed below areintended to include all such forms, and are commercially available orcan be prepared using conventional procedures and reagents.

In one embodiment, a compound of the invention is administered incombination with a diuretic. Representative diuretics include, but arenot limited to: carbonic anhydrase inhibitors such as acetazolamide anddichlorphenamide; loop diuretics, which include sulfonamide derivativessuch as acetazolamide, ambuside, azosemide, bumetanide, butazolamide,chloraminophenamide, clofenamide, clopamide, clorexolone, disulfamide,ethoxolamide, furosemide, mefruside, methazolamide, piretanide,torsemide, tripamide, and xipamide, as well as non-sulfonamide diureticssuch as ethacrynic acid and other phenoxyacetic acid compounds such astienilic acid, indacrinone and quincarbate; osmotic diuretics such asmannitol; potassium-sparing diuretics, which include aldosteroneantagonists such as spironolactone, and Na⁺ channel inhibitors such asamiloride and triamterene; thiazide and thiazide-like diuretics such asalthiazide, bendroflumethiazide, benzylhydrochlorothiazide,benzthiazide, buthiazide, chlorthalidone, chlorothiazide,cyclopenthiazide, cyclothiazide, epithiazide, ethiazide, fenquizone,flumethiazide, hydrochlorothiazide, hydroflumethiazide, indapamide,methylclothiazide, meticrane, metolazone, paraflutizide, polythiazide,quinethazone, teclothiazide, and trichloromethiazide; and combinationsthereof. In a particular embodiment, the diuretic is selected fromamiloride, bumetanide, chlorothiazide, chlorthalidone, dichlorphenamide,ethacrynic acid, furosemide, hydrochlorothiazide, hydroflumethiazide,indapamide, methylclothiazide, metolazone, torsemide, triamterene, andcombinations thereof. The diuretic will be administered in an amountsufficient to provide from about 5-50 mg per day, more typically 6-25 mgper day, with common dosages being 6.25 mg, 12.5 mg or 25 mg per day.

Compounds of the invention may also be administered in combination witha adrenergic receptor blocker. Representative β₁ adrenergic receptorblockers include, but are not limited to, acebutolol, alprenolol,amosulalol, arotinolol, atenolol, befunolol, betaxolol, bevantolol,bisoprolol, bopindolol, bucindolol, bucumolol, bufetolol, bufuralol,bunitrolol, bupranolol, bubridine, butofilolol, carazolol, carteolol,carvedilol, celiprolol, cetamolol, cloranolol, dilevalol, epanolol,esmolol, indenolol, labetolol, levobunolol, mepindolol, metipranolol,metoprolol such as metoprolol succinate or metoprolol tartrate,moprolol, nadolol, nadoxolol, nebivalol, nipradilol, oxprenolol,penbutolol, perbutolol, pindolol, practolol, pronethalol, propranolol,sotalol, sufinalol, talindol, tertatolol, tilisolol, timolol,toliprolol, xibenolol, and combinations thereof. In one particularembodiment, the β₁ adrenergic receptor blocker is selected fromatenolol, bisoprolol, metoprolol, propranolol, sotalol, and combinationsthereof.

In one embodiment, a compound of the invention is administered incombination with a calcium channel blocker. Representative calciumchannel blockers include, but are not limited to, amlodipine, anipamil,aranipine, barnidipine, bencyclane, benidipine, bepridil, clentiazem,cilnidipine, cinnarizine, diltiazem, efonidipine, elgodipine, etafenone,felodipine, fendiline, flunarizine, gallopamil, isradipine, lacidipine,lercanidipine, lidoflazine, lomerizine, manidipine, mibefradil,nicardipine, nifedipine, niguldipine, niludipine, nilvadipine,nimodipine, nisoldipine, nitrendipine, nivaldipine, perhexyline,prenylamine, ryosidine, semotiadil, terodiline, tiapamil, verapamil, andcombinations thereof. In one particular embodiment, the calcium channelblocker is selected from amlodipine, bepridil, diltiazem, felodipine,isradipine, lacidipine, nicardipine, nifedipine, niguldipine,niludipine, nimodipine, nisoldipine, ryosidine, verapamil, andcombinations thereof.

Compounds of the invention can also be administered in combination withan angiotensin-converting enzyme (ACE) inhibitor. Representative ACEinhibitors include, but are not limited to, accupril, alacepril,benazepril, benazeprilat, captopril, ceranapril, cilazapril, delapril,enalapril, enalaprilat, fosinopril, fosinoprilat, imidapril, lisinopril,moexipril, monopril, moveltopril, pentopril, perindopril, quinapril,quinaprilat, ramipril, ramiprilat, saralasin acetate, spirapril,temocapril, trandolapril, zofenopril, and combinations thereof. In aparticular embodiment, the ACE inhibitor is selected from benazepril,enalapril, lisinopril, ramipril, and combinations thereof.

In one embodiment, a compound of the invention is administered incombination with an AT₁ receptor antagonist, also known as anangiotensin II type 1 receptor blocker (ARB). Representative ARBsinclude, but are not limited to, abitesartan, benzyllosartan,candesartan, candesartan cilexetil, elisartan, embusartan,enoltasosartan, eprosartan, fonsartan, forasartan, glycyllosartan,irbesartan, isoteoline, losartan, medoximil, milfasartan, olmesartan,opomisartan, pratosartan, ripisartan, saprisartan, saralasin, sarmesin,tasosartan, telmisartan, valsartan, zolasartan, and combinationsthereof. In a particular embodiment, the ARB is selected fromcandesartan, eprosartan, irbesartan, losartan, olmesartan, saprisartan,tasosartan, telmisartan, valsartan, and combinations thereof. Exemplarysalts include candesartan cilexetil, eprosartan mesylate, losartanpotassium salt, and olmesartan medoxomil. Typically, the ARB will beadministered in an amount sufficient to provide from about 4-600 mg perdose, with exemplary daily dosages ranging from 20-320 mg per day.

In another embodiment, a compound of the invention is administered incombination with a neprilysin (NEP) inhibitor. Representative NEPinhibitors include, but are not limited to: candoxatril; candoxatrilat;dexecadotril ((+)-N-[2(R)-(acetylthiomethyl)-3-phenylpropionyl]glycinebenzyl ester); CGS-24128(3-[3-(biphenyl-4-yl)-2-(phosphonomethylamino)propionamido]propionicacid); CGS-24592((S)-3-[3-(biphenyl-4-yl)-2-(phosphonomethylamino)propionamido]propionicacid); CGS-25155(N-[9(R)-(acetylthiomethyl)-10-oxo-1-azacyclodecan-2(S)-ylcarbonyl]-4(R)-hydroxy-L-prolinebenzyl ester); 3-(1-carbamoylcyclohexyl)propionic acid derivativesdescribed in WO 2006/027680 to Hepworth et al. (Pfizer Inc.); JMV-390-1(2(R)-benzyl-3-(N-hydroxycarbamoyl)propionyl-L-isoleucyl-L-leucine);ecadotril; phosphoramidon; retrothiorphan; RU-42827(2-(mercaptomethyl)-N-(4-pyridinyl)benzenepropionamide); RU-44004(N-(4-morpholinyl)-3-phenyl-2-(sulfanylmethyl)propionamide); SCH-32615((S)—N—[N-(1-carboxy-2-phenylethyl)-L-phenylalanyl]-β-alanine) and itsprodrug SCH-34826((S)—N—[N-[1-[[(2,2-dimethyl-1,3-dioxolan-4-yl)methoxy]carbonyl]-2-phenylethyl]-L-phenylalanyl]-β-alanine);sialorphin; SCH-42495(N-[2(S)-(acetylsulfanylmethyl)-3-(2-methylphenyl)propionyl]-L-methionineethyl ester); spinorphin; SQ-28132(N-[2-(mercaptomethyl)-1-oxo-3-phenylpropyl]leucine); SQ-28603(N-[2-(mercaptomethyl)-1-oxo-3-phenylpropyl]-β-alanine); SQ-29072(7-[[2-(mercaptomethyl)-1-oxo-3-phenylpropyl]amino]heptanoic acid);thiorphan and its prodrug racecadotril; UK-69578(cis-4-[[[1-[2-carboxy-3-(2-methoxyethoxy)propyl]cyclopentyl]carbonyl]amino]cyclohexanecarboxylicacid); and combinations thereof. In a particular embodiment, the NEPinhibitor is selected from candoxatril, candoxatrilat, CGS-24128,phosphoramidon, SCH-32615, SCH-34826, SQ-28603, thiorphan, andcombinations thereof. The NEP inhibitor will be administered in anamount sufficient to provide from about 20-800 mg per day, with typicaldaily dosages ranging from 50-700 mg per day, more commonly 100-600 or100-300 mg per day.

In yet another embodiment, a compound of the invention is administeredin combination with a non-steroidal anti-inflammatory agent (NSAID).Representative NSAIDs include, but are not limited to, acemetacin,acetyl salicylic acid, alclofenac, alminoprofen, amfenac, amiprilose,amoxiprin, anirolac, apazone, azapropazone, benorilate, benoxaprofen,bezpiperylon, broperamole, bucloxic acid, carprofen, clidanac,diclofenac, diflunisal, diftalone, enolicam, etodolac, etoricoxib,fenbufen, fenclofenac, fenclozic acid, fenoprofen, fentiazac, feprazone,flufenamic acid, flufenisal, fluprofen, flurbiprofen, furofenac,ibufenac, ibuprofen, indomethacin, indoprofen, isoxepac, isoxicam,ketoprofen, ketorolac, lofemizole, lomoxicam, meclofenamate,meclofenamic acid, mefenamic acid, meloxicam, mesalamine, miroprofen,mofebutazone, nabumetone, naproxen, niflumic acid, oxaprozin, oxpinac,oxyphenbutazone, phenylbutazone, piroxicam, pirprofen, pranoprofen,salsalate, sudoxicam, sulfasalazine, sulindac, suprofen, tenoxicam,tiopinac, tiaprofenic acid, tioxaprofen, tolfenamic acid, tolmetin,triflumidate, zidometacin, zomepirac, and combinations thereof. In aparticular embodiment, the NSAID is selected from etodolac,flurbiprofen, ibuprofen, indomethacin, ketoprofen, ketorolac, meloxicam,naproxen, oxaprozin, piroxicam, and combinations thereof.

In yet another embodiment, a compound of the invention is administeredin combination with an anti-lipid agent. Representative anti-lipidagents include, but are not limited to: statins such as atorvastatin,fluvastatin, lovastatin, pravastatin, rosuvastatin and simvastatin;cholesteryl ester transfer proteins (CETPs); and combinations thereof.

In yet another embodiment, a compound of the invention is administeredin combination with an anti-diabetic agent. Representative anti-diabeticagents include, but are not limited to: injectable drugs such as insulinand insulin derivatives; orally effective drugs including biguanidessuch as metformin, glucagon antagonists, α-glucosidase inhibitors suchas acarbose and miglitol, meglitinides such as repaglinide,oxadiazolidinediones, sulfonylureas such as chlorpropamide, glimepiride,glipizide, glyburide and tolazamide, thiazolidinediones such aspioglitazone and rosiglitazone; and combinations thereof.

In one embodiment, a compound of the invention is administered incombination with an anti-thrombotic agent, representative examples ofwhich include, but are not limited to, aspirin, anti-platelet agents,heparin, and combinations thereof. Compounds of the invention may alsobe administered in combination with a renin inhibitor, examples of whichinclude, but are not limited to, aliskiren, enalkiren, remikiren, andcombinations thereof. In another embodiment, a compound of the inventionis administered in combination with an endothelin receptor antagonist,representative examples of which include, but are not limited to,bosentan, darusentan, tezosentan, and combinations thereof. Compounds ofthe invention may also be administered in combination with an endothelinconverting enzyme inhibitor, examples of which include, but are notlimited to, phosphoramidon, CGS 26303, and combinations thereof. In yetanother embodiment, a compound of the invention is administered incombination with an aldosterone antagonist, representative examples ofwhich include, but are not limited to, eplerenone, spironolactone, andcombinations thereof.

Combined therapeutic agents may also be helpful in further combinationtherapy with compounds of the invention. For example, a combination ofthe ACE inhibitor enalapril (in the maleate salt form) and the diuretichydrochlorothiazide, which is sold under the mark Vaseretic®, or acombination of the calcium channel blocker amlodipine (in the besylatesalt form) and the ARB olmesartan (in the medoxomil prodrug form), or acombination of a calcium channel blocker and a statin, all may also beused with the compounds of the invention. Dual-acting agents may also behelpful in combination therapy with compounds of the invention. Forexample, angiotensin-converting enzyme/neprilysin (ACE/NEP) inhibitorssuch as: AVE-0848((4S,7S,12bR)-7-[3-methyl-2(S)-sulfanylbutyramido]-6-oxo-1,2,3,4,6,7,8,12b-octahydropyrido[2,1-a][2]benzazepine-4-carboxylicacid); AVE-7688 (ilepatril) and its parent compound; BMS-182657(2-[2-oxo-3(S)-[3-phenyl-2(S)-sulfanylpropionamido]-2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl]aceticacid); CGS-26303([N-[2-(biphenyl-4-yl)-1(S)-(1H-tetrazol-5-yl)ethyl]amino]methylphosphonicacid); CGS-35601(N-[1-[4-methyl-2(S)-sulfanylpentanamido]cyclopentylcarbonyl]-L-tryptophan);fasidotril; fasidotrilate; enalaprilat; ER-32935((3R,6S,9aR)-6-[3(S)-methyl-2(S)-sulfanylpentanamido]-5-oxoperhydrothiazolo[3,2-a]azepine-3-carboxylicacid); gempatrilat; MDL-101264((4S,7S,12bR)-7-[2(S)-(2-morpholinoacetylthio)-3-phenylpropionamido]-6-oxo-1,2,3,4,6,7,8,12b-octahydropyrido[2,1-a][2]benzazepine-4-carboxylicacid); MDL-101287 ([4S-[4α,7α(R*),12bβ]]-7-[2-(carboxymethyl)-3-phenylpropionamido]-6-oxo-1,2,3,4,6,7,8,12b-octahydropyrido[2,1-a][2]benzazepine-4-carboxylicacid); omapatrilat; RB-105(N-[2(S)-(mercaptomethyl)-3(R)-phenylbutyl]-L-alanine); sampatrilat;SA-898((2R,4R)—N-[2-(2-hydroxyphenyl)-3-(3-mercaptopropionyl)thiazolidin-4-ylcarbonyl]-L-phenylalanine);Sch-50690(N-[1(S)-carboxy-2-[N2-(methanesulfonyl)-L-lysylamino]ethyl]-L-valyl-L-tyrosine);and combinations thereof, may also be included. In one particularembodiment, the ACE/NEP inhibitor is selected from: AVE-7688,enalaprilat, fasidotril, fasidotrilate, omapatrilat, sampatrilat, andcombinations thereof.

Other therapeutic agents such as α₂-adrenergic receptor agonists andvasopressin receptor antagonists may also be helpful in combinationtherapy. Exemplary α₂-adrenergic receptor agonists include clonidine,dexmedetomidine, and guanfacine. Exemplary vasopressin receptorantagonists include tolvaptan.

The following formulations illustrate representative pharmaceuticalcompositions of the invention.

Exemplary Hard Gelatin Capsules for Oral Administration

A compound of the invention (50 g), 440 g spray-dried lactose, and 10 gmagnesium stearate are thoroughly blended. The resulting composition isthen loaded into hard gelatin capsules to provide 500 mg of compositionper capsule. Alternately, 20 mg of a compound of the invention isthoroughly blended with 89 mg starch, 89 mg microcrystalline cellulose,and 2 mg magnesium stearate. The mixture is then passed through a No. 45mesh U.S. sieve and loaded into a hard gelatin capsule having 200 mg ofcomposition per capsule.

Exemplary Gelatin Capsule Formulation for Oral Administration

A compound of the invention (100 mg) is thoroughly blended with 50 mgpolyoxyethylene sorbitan monooleate and 250 mg starch powder. Themixture is then loaded into a gelatin capsule to provide 300 mg ofcomposition per capsule. Alternately, 40 mg of a compound of theinvention is thoroughly blended with 260 mg microcrystalline cellulose(Avicel PH 103) and 0.8 mg magnesium stearate. The mixture is thenloaded into a gelatin capsule (Size #1, White, Opaque) having 300 mg ofcomposition per capsule.

Exemplary Tablet Formulation for Oral Administration

A compound of the invention (10 mg), 45 mg starch, and 35 mgmicrocrystalline cellulose are passed through a No. 20 mesh U.S. sieveand mixed thoroughly. The granules so produced are dried at 50-60° C.and passed through a No. 16 mesh U.S. sieve. A solution ofpolyvinylpyrrolidone (4 mg as a 10% solution in sterile water) is mixedwith 4.5 mg sodium carboxymethyl starch, 0.5 mg magnesium stearate, and1 mg talc, and this mixture is then passed through a No. 16 mesh U.S.sieve. The sodium carboxymethyl starch, magnesium stearate and talc arethen added to the granules. After mixing, the mixture is compressed on atablet machine to afford a tablet weighing 100 mg.

Alternately, 250 mg of a compound of the invention is thoroughly blendedwith 400 mg microcrystalline cellulose, 10 mg silicon dioxide (fumed),and 5 mg stearic acid. The mixture is then compressed to form tabletshaving 665 mg of composition per tablet.

Alternately, 400 mg of a compound of the invention is thoroughly blendedwith 50 mg cornstarch, 25 mg croscarmellose sodium, 120 mg lactose, and5 mg magnesium stearate. The mixture is then compressed to form asingle-scored tablet having 600 mg of composition per tablet.

Alternately, 100 mg of a compound of the invention is thoroughly blendedwith 100 mg cornstarch and an aqueous solution of gelatin (20 mg). Themixture is dried and ground to a fine powder. Microcrystalline cellulose(50 mg) and 5 mg magnesium stearate are the admixed with the gelatinformulation, granulated and the resulting mixture compressed to formtablets having 100 mg of active agent per tablet.

Exemplary Suspension Formulation for Oral Administration

The following ingredients are mixed to form a suspension containing 100mg of active agent per 10 mL of suspension:

Ingredients Amount Compound of the invention 1.0 g Fumaric acid 0.5 gSodium chloride 2.0 g Methyl paraben 0.15 g Propyl paraben 0.05 gGranulated sugar 25.5 g Sorbitol (70% solution) 12.85 g Veegum ® K(magnesium aluminum silicate) 1.0 g Flavoring 0.035 mL Colorings 0.5 mgDistilled water q.s. to 100 mL

Exemplary Injectable Formulation for Administration by Injection

A compound of the invention (0.2 g) is blended with 0.4 M sodium acetatebuffer solution (2.0 mL). The pH of the resulting solution is adjustedto pH 4 using 0.5 N aqueous HCL or 0.5 N aqueous NaOH, as necessary, andthen sufficient water for injection is added to provide a total volumeof 20 mL. The mixture is then filtered through a sterile 0.22 μm filterto provide a sterile solution suitable for administration by injection.

Exemplary Compositions for Administration by Inhalation

A compound of the invention (0.2 mg) is micronized and then blended with25 mg lactose. This blended mixture is then loaded into a gelatininhalation cartridge. The contents of the cartridge are administeredusing a dry powder inhaler, for example.

Alternately, a micronized compound of the invention (10 g) is dispersedin a solution prepared by dissolving 0.2 g lecithin in 200 mLdemineralized water. The resulting suspension is spray dried and thenmicronized to form a micronized composition comprising particles havinga mean diameter less than about 1.5 μm. The micronized composition isthen loaded into metered-dose inhaler cartridges containing pressurized1,1,1,2-tetrafluoroethane in an amount sufficient to provide about 10 μgto about 500 μg of active agent per dose when administered by theinhaler.

Alternately, 25 mg of a compound of the invention is dissolved in 125 mLcitrate buffered (pH 5) isotonic saline. The mixture is stirred andsonicated until the compound is dissolved. The pH of the solution ischecked and adjusted, if necessary, to pH 5 by slowly adding aqueous 1NNaOH. The solution is administered using a nebulizer device thatprovides about 10 μg to about 500 μg of active agent per dose.

EXAMPLES

The following Preparations and Examples are provided to illustratespecific embodiments of the invention. These specific embodiments,however, are not intended to limit the scope of the invention in any wayunless specifically indicated.

The following abbreviations have the following meanings unless otherwiseindicated and any other abbreviations used herein and not defined havetheir standard meaning:

-   -   ACE angiotensin converting enzyme    -   AcOH acetic acid    -   APP aminopeptidase P    -   AT₁ angiotensin II type 1 (receptor)    -   AT₂ angiotensin II type 2 (receptor)    -   BCA bicinchoninic acid    -   BOP benzotriazol-1-yloxytris(dimethylamino)phosphonium        hexafluorophosphate    -   BSA bovine serum albumin    -   DCM dichloromethane (methylene chloride)    -   DIPEA N,N-diisopropylethylamine    -   DMF dimethylformamide    -   DMSO dimethyl sulfoxide    -   Dnp 2,4-dinitrophenyl    -   DOCA deoxycorticosterone acetate    -   EDTA ethylenediaminetetraacetic acid    -   EGTA ethylene glycol bis(O-aminoethyl        ether)-N,N,N′N′-tetraacetic acid    -   EtOAc ethyl acetate    -   EtOH ethanol    -   HATU O-(7-azabenzotriazol-1-yl-N,N,N′,N′-tetramethyluronium        hexafluorophosphate    -   Mca (7-methoxycoumarin-4-yl)acyl    -   MeOH methanol    -   NBS N-bromosuccinimide    -   NEP neprilysin (EC 3.4.24.11)    -   PBS phosphate buffered saline    -   SHR spontaneously hypertensive rat    -   TFA trifluoroacetic acid    -   THF tetrahydrofuran    -   Tris tris(hydroxymethyl)aminomethane    -   Tween-20 polyethylene glycol sorbitan monolaurate

Any other abbreviations used herein but not defined have their standard,generally accepted meaning. Unless noted otherwise, all materials, suchas reagents, starting materials and solvents, were purchased fromcommercial suppliers (such as Sigma-Aldrich, Fluka Riedel-de Haën, andthe like) and were used without further purification.

Preparation 1 5-(4′-Bromomethylbiphenyl-2-yl)-1-trityl-1H-tetrazole

To a nitrogen-saturated suspension ofN-triphenylmethyl-5-[4′-methylbiphenyl-2-yl]tetrazole (10 g, 20.9 mmol)in DCM was added NBS (3.7 g, 20.9 mmol) and a catalytic amount ofbenzoyl peroxide (60 mg, 0.2 mmol). The mixture was stirred at refluxfor 15 hours. After cooling to room temperature, the precipitate wasfiltered and the organic solution was concentrated in vacuo. Silica gelchromatography (EtOAc/hexane) gave the title compound as a white solid.

¹H-NMR (400 MHz, DMSO-d₆): δ (ppm) 4.61 (s, 2H), 6.80 (d, 6H), 7.01 (d,2H), 7.24 (d, 2H), 7.28-7.35 (m, 9H), 7.43-7.45 (dd, 1H), 7.50-7.56 (td,1H), 7.58-7.60 (td, 1H), 7.77-7.79 (dd, 1H).

Example 1 2-Mercaptomethyl-4-methylpentanoic Acid(2-Butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl)amide

(2-[2′-(1-Trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl)carbamicacid t-butyl ester (1a): A solution of5-(4′-bromomethylbiphenyl-2-yl)-1-trityl-1H-tetrazole made as describedin Preparation 1 (23.2 g, 41.6 mmol),N-(2-aminoethyl)(t-butoxy)carboxamide (20 g, 125 mmol), and potassiumcarbonate (8.6 g, 62.4 mmol) in THF (100 mL) was stirred at roomtemperature for 48 hours. The mixture was concentrated in vacuo andextracted with 1M aqueous KOH (20 mL) and EtOAc (2×200 mL). The combinedorganic extracts were dried over Na₂SO₄, filtered, and concentrated invacuo. Intermediate (1a) was used without further purification.

(2-Butyryl-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl)carbamicacid t-butyl ester (1b) andN-(2-aminoethyl)-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramideas the TFA salt (1c): Butyryl chloride (1.5 mL, 14.8 mmol) was added toa solution of intermediate (1a) (8.6 g, 13.5 mmol) in toluene (70 mL) at0° C. followed by the addition of DIPEA (7.1 mL, 40.5 mmol). The mixturewas stirred for 1 hour at room temperature. 1M aqueous NaOH (10 mL) wasadded and the solution concentrated in vacuo. The concentrate wasextracted with EtOAc (2×100 mL) and water (75 mL). The combined organicextracts were dried over Na₂SO₄, filtered, and concentrated in vacuo toafford intermediate (1b). A solution of intermediate (1b), 1,4-dioxane(50 mL) and 4M HCl in 1,4-dioxane (50 mL) was stirred at roomtemperature for 3 hours. The precipitate was filtered and purified byreverse phase HPLC to afford intermediate (1c) (22% yield).

Thioacetic acidS-[2-(2-butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethylcarbamoyl)-4-methylpentyl]ester(1d) and title compound: BOP (305 mg, 0.7 mmol) was added to a solutionof intermediate (1c) (300 mg), 2-acetylsulfanylmethyl-4-methylpentanoicacid (141 mg, 0.7 mmol), and DIPEA (0.15 mL) in DMF (4 mL) at roomtemperature. After 5 minutes, DIPEA (0.13 mL) was added and the solutionwas stirred overnight. The mixture was concentrated in vacuo to affordthe crude intermediate (1d), which was then dissolved in MeOH (2 mL), 1Maqueous NaOH (2 mL) and 6M aqueous NaOH (0.4 mL) under nitrogen at roomtemperature. After 3 hours, the mixture was neutralized with 6M aqueousHCl and was concentrated in vacuo. Reverse phase HPLC gave the titlecompound (75% yield). MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26.found, 509.2.

¹H NMR (CDCl₃) δ (ppm) 0.8-1.0 (m, 6H), 1.0-1.1 (m, 3H), 1.2-1.3 (m,1H), 1.4-1.5 (m, 3H), 1.7-1.9 (m, 2H), 2.2-2.3 (m, 1H), 2.5-2.7 (m, 6H),3.5-3.7 (m, 2H), 4.5-4.7 (m, 2H), 7.1-7.2 (m, 3H), 7.2-7.3 (m, 2H),7.5-7.7 (m, 3H), 7.9 (d, 1H).

Example 2N-Hydroxy-2-isobutyl-N′-(2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)malonamide

(2-[2′-(1-Trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl)carbamicacid t-butyl ester (2a): A solution of5-(4′-bromomethylbiphenyl-2-yl)-1-trityl-1H-tetrazole made as describedin Preparation 1 (20.9 g, 37.4 mmol), N-(2-aminoethyl)(t-butoxy)carboxamide (15 g, 93.6 mmol), and potassium carbonate (10.4 g, 74.9mmol) in THF (150 mL) was stirred overnight at room temperature. Thesolvent was removed in vacuo and extracted with 1M aqueous KOH (70 mL)and DCM (3×200 mL). The combined organic extracts were dried over MgSO₄,filtered, and concentrated in vacuo. The crude intermediate (2a) wasused in the next step.

(2-Pentanoyl-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl) carbamic acid t-butyl ester (2b):Valeryl chloride (1.4 mL, 12.2 mmol) was added to a solution ofintermediate (2a) (7.1 g, 11.1 mmol) in toluene (80 mL) at 0° C.followed by the addition of DIPEA (5.8 mL, 33.2 mmol). After 2 hours atroom temperature, 1M aqueous NaOH (20 mL) was added and the mixture wasconcentrated in vacuo. The concentrate was extracted with EtOAc (2×100mL) and water (50 mL). The combined organic extracts were dried overMgSO₄ and concentrated in vacuo (75.3% yield). The crude intermediate(2b) was used in the next step.

Pentanoic acid(2-aminoethyl)-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide as theTFA salt (2c): A solution of the crude intermediate (2b) (6.5 g, 9 mmol)in 1,4-dioxane (50 mL) and 4M HCl in 1,4-dioxane (50 mL) was stirred atroom temperature for 4 hours. The precipitate was filtered and purifiedby reverse phase HPLC to afford intermediate (2c) (81.8% yield).

N-(2,2-Dimethyl-1-propionyloxy)-2-isobutyl-N′-(2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)malonamide(2d): HATU (46 mg) was added to intermediate (2c) (50 mg),2-(2,2-dimethylpropionyloxycarbamoyl)-4-methyl pentanoic acid (31 mg),and DIPEA (0.02 mL) in DMF (1 mL), and was stirred at room temperaturefor 10 minutes. DIPEA (0.02 mL) was added and the mixture was stirredovernight. The mixture was concentrated and crude intermediate (2d) wasused in the next step.

Title compound: Intermediate (2d) in MeOH (1 mL), 1M aqueous NaOH (1mL), and 6M aqueous NaOH (0.3 mL) was stirred under nitrogen overnight.The mixture was neutralized with 6M aqueous HCl and concentrated invacuo. Reverse phase HPLC gave the title compound. MS m/z: [M+H⁺] calcdfor C₂₈H₃₇N₇O₄, 536.29. found 536.4.

Preparation 2 4′-Bromomethylbiphenyl-2-carboxylic Acid t-Butyl Ester

A solution of 4′-methylbiphenyl-2-carboxylic acid (48.7 g, 230 mmol) andthionyl chloride (150 mL) was stirred at room temperature. After 5.5hours, the mixture was concentrated in vacuo. Excess thionyl chloridewas removed by co-distillation with toluene to afford a yellow solid(52.6 g). The material was then dissolved in THF (500 mL) and cooled to0° C. Potassium t-butoxide (15 g, 130 mmol) was added portion wise,followed by a 1M solution of potassium t-butoxide in THF (250 mL).Additional solid potassium t-butoxide (21.4 g, 100 mmol) was added andthe mixture was stirred at 0° C. for 1.5 hours. The mixture waspartitioned between EtOAc and water. The organic layer was washed withsaturated aqueous NaCl, dried over MgSO₄, filtered, and concentrated toafford 4′-methylbiphenyl-2-carboxylic acid t-butyl ester (62.3 g) as ayellow oil, which was used directly in the next step.

Benzoyl peroxide (3.9 g, 16 mmol) was added to a solution of the aboveoil (62 g, 230 mmol) in benzene (800 mL) and NBS (41.2 g, 230 mmol) andwas heated at reflux. After 4.5 hours, benzoyl peroxide (1 g) was added,followed by NBS (16 g, 66 mmol) 30 minutes later. The mixture wasstirred for a total of 6 hours and then cooled, filtered, andconcentrated in vacuo. The resulting residue was then crystallized fromdiethyl ether and hexane at 4° C. overnight to give the title compound(40.7 g) as a pale yellow solid.

¹H NMR (DMSO) δ (ppm) 1.1 (s, 9H), 4.6 (s, 2H), 7.1-7.6 (m, 8H).

Example 34′-({[2-(2-Mercaptomethyl-3-phenylpropionylamino)ethyl]pentanoylamino}methyl)biphenyl-2-carboxylicAcid (3-1; R⁶=benzyl) and4′-({[2-(2-Mercaptomethyl-4-methylpentanoylamino)ethyl]pentanoylamino}methyl)biphenyl-2-carboxylicAcid (3-2; R⁶=i-butyl)

4′-[(2-t-Butoxycarbonylaminoethylamino)methyl]biphenyl-2-carboxylic acidt-butyl ester (3a): A solution of 4′-bromomethylbiphenyl-2-carboxylicacid t-butyl ester made as described in Preparation 2 (7.2 g, 20.8mmol), N-(2-aminoethyl) (t-butoxy)carboxamide (10 g, 62.4 mmol), andpotassium carbonate (4.3 g, 31.2 mmol) in THF (40 mL) was stirred atroom temperature overnight. The mixture was concentrated then extractedwith EtOAc (3×150 mL) and water (80 mL). The combined organic extractswere dried over Na₂SO₄, filtered, and concentrated in vacuo to affordcrude intermediate (3a) (98.4% yield), which was used in the next stepwithout further purification.

4′-[(2-t-Butoxycarbonylaminoethyl)pentanoylamino]methylbiphenyl-2-carboxylicacid t-butyl ester (3b) and4′-[(2-aminoethyl)pentanoylamino]methylbiphenyl-2-carboxylic acid (3c):Valeryl chloride (4.6 mL, 38.7 mmol) was added to a solution of crudeintermediate (3a) (15 g, 35.2 mmol) in toluene (100 mL) at 0° C.followed by the addition of DIPEA (18.4 mL, 105 mmol). The mixture wasstirred at room temperature for 3 hours. 1M aqueous NaOH (10 mL) wasadded and the mixture was concentrated in vacuo. The concentrate wasextracted with EtOAc (3×150 mL) and water (80 mL). The organic extractswere dried over Na₂SO₄, filtered, and concentrated in vacuo to affordcrude intermediate (3b). A solution of crude intermediate (3b),1,4-dioxane (50 mL) and 4M HCl in 1,4-dioxane (50 mL) was stirred for 40minutes at room temperature. The precipitate was filtered and purifiedby reverse phase HPLC to afford intermediate (3c).

Title compounds (3-1) and (3-2): In two separate vials. HATU (47.2 mg,124 μmol) was added to a solution of2-acetylsulfanylmethyl-4-methylpentanoic acid (25.4 mg, 124 μmol) or2-acetylsulfanylmethyl-3-phenylpropionic acid (29.6 mg, 124 μmol) in DMF(0.3 ml) and DIPEA (27 μL). The solutions were stirred at roomtemperature for 15 minutes before the addition of a solution ofintermediate (3c) (40 mg, 0.1 mmol) in DMF (0.3 mL) to each solution.The solutions were stirred for a further 3 hours. The solutions wereconcentrated in vacuo to afford intermediates, which were each dissolvedin MeOH (1 mL), 1M aqueous NaOH (1 mL), and 6M aqueous NaOH (0.2 mL) intwo separate vials. The mixtures were stirred at room temperature undernitrogen for 3 hours. The mixtures were neutralized with 6M aqueous HCland concentrated in vacuo. Reverse phase HPLC gave the title compounds:

(3-1) MS m/z: [M+H⁺] calcd for C₃₁H₃₆N₂O₄S, 533.24. found 533.2. and

(3-2) MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₂O₄S, 499.26. found 499.2.

Example 44-({[2-(2-Mercaptomethyl-3-phenylpropionylamino)ethyl]pentanoylamino}methyl)benzoicAcid (4-1; R⁵=—CH—SH; R⁶=benzyl),4-({[2-((S)-2-mercapto-3-phenylpropionylamino)ethyl]pentanoylamino}methyl)benzoicAcid (4-2; R⁵=—SH; R⁶=benzyl),4-({[2-(2-Mercaptomethyl-4-methylpentanoylamino)ethyl]pentanoylamino}methyl)benzoicAcid (4-3; R⁵=—CH₂SH; R⁶=i-butyl),4-({[2-(2-Mercaptomethyl-3-methylbutyrylaminoethyl]pentanoylamino}methyl)benzoicAcid (4-4; R⁵=—CH₂SH; R⁶=i-propyl), and4-({[2-(3-Mercapto-2-methylpropionylamino)ethyl]pentanoylamino}methyl)benzoicAcid (4-5; R⁵=—CH₂SH; R⁶=methyl)

4-{[(2-t-Butoxycarbonylaminoethylamino)methylbenzoic acid methyl ester(4a): A solution of methyl 4-bromomethylbenzoate (10 g),N-(2-aminoethyl)(t-butoxy) carboxamide (28 g), and potassium carbonate(9.1 g) in THF (200 mL) was stirred at room temperature overnight. Themixture was concentrated and extracted with DCM (2×200 mL) and water (60mL). The combined organic extracts were dried over Na₂SO₄, filtered, andconcentrated in vacuo to afford the crude intermediate (4a) (87.8%yield), which was used without further purification.

4-{[(2-t-Butoxycarbonylaminoethyl)pentanoylamino]methyl}benzoic acidmethyl ester (4b) and 4-[(2-aminoethyl)pentanoylamino]methylbenzoic acidmethyl ester as the TFA salt (4c): DIPEA (10.6 mL, 60.9 mmol) was addedto a solution of the crude intermediate (4a) (6.3 g, 20.3 mmol) andvaleryl chloride (2.7 mL, 22.3 mmol) in toluene (80 mL) at 0° C. Themixture was stirred for 3 hours at room temperature. 1M aqueous NaOH (5mL) was added to the mixture at 0° C. and the resulting solution wasconcentrated in vacuo. The concentrate was extracted with EtOAc (3×70mL) and water (40 mL). The combined organic extracts were dried overMgSO₄, filtered, and concentrated in vacuo giving intermediate (4b)(87.8%). Intermediate (4b) (7 g) was dissolved in 1,4-dioxane (50 mL)and 4M HCl in 1,4-dioxane (50 mL) at room temperature. After 3 hours,the precipitate was filtered. Reverse phase HPLC gave intermediate (4c)(54.1% yield).

Title compounds (4-1), (4-2), (4-3), (4-4) and (4-5): BOP (99.8 mg, 226μmol) was added to a solution of intermediate (4c), DIPEA (0.1 mL) inDMF (1 mL), and either 2-acetylsulfanylmethyl-3-phenylpropionic acid(53.8 mg, 226 μmol), (S)-2-acetylsulfanyl-3-phenylpropionic acid (50.6mg, 226 μmol), 2-acetylsulfanylmethyl-4-methylpentanoic acid (46.1 mg,226 μmol), 2-acetylsulfanylmethyl-3-methylbutyric acid (42.9 mg, 226μmol), or 3-acetylsulfanyl-2-methylpropionic acid (36.6 mg, 226 μmol),to 5 separate 20 mL vials at room temperature. Additional DIPEA (0.1 mL)was added to each vial after 5 minutes. After 3 hours, the mixtures wereconcentrated and each intermediate was used without further purificationin the next step. The concentrate of each mixture was dissolvedseparately in MeOH (1 mL), 1M aqueous NaOH, and 6M aqueous NaOH (0.2mL), and was stirred under an atmosphere of nitrogen for 4 hours. Eachmixture was neutralized with 6M aqueous HCl and concentrated in vacuo.Reverse phase HPLC gave the title compounds:

(4-1) MS m/z: [M+H⁺] calcd for C₂₅H₃₂N₂O₄S, 457.21. found 457.2.

(4-2) MS m/z: [M+H⁺] calcd for C₂₄H₃₀N₂O₄S, 443.19. found 443.2.

(4-3) MS m/z: [M+H⁺] calcd for C₂₂H₃₄N₂O₄S, 423.22. found 423.2.

(4-4) MS m/z: [M+H⁺] calcd for C₂₁H₃₂N₂O₄S, 409.21. found 409.2. and

(4-5) MS m/z: [M+H⁺] calcd for C₁₉H₂₈N₂O₄S, 381.18. found 381.2.

Example 5 2-Mercaptomethyl-4-methylpentanoic Acid((S)-2-{Butyryl[2′-(1H-tetrazol-5-ylbiphenyl-4-ylmethyl]amino}propyl)amide (5-1)

(S)-2-[2′-(1-Trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminopropan-1-ol(5a): A solution of5-(4′-bromomethylbiphenyl-2-yl)-1-trityl-1H-tetrazole made as describedin Preparation 1 (9.7 g, 17.4 mmol), (2S)-2-aminopropan-1-ol (3.9 g,52.3 mmol), and potassium carbonate (2.4 g, 17.4 mmol), in THF (170 mL)was stirred at room temperature overnight. Water (100 mL) was added, andthe aqueous phase was extracted with EtOAc (3×100 mL). The combinedorganic extracts were dried over MgSO₄, filtered, and concentrated invacuo. Silica gel chromatography gave intermediate (5a).

N—((S)-2-Hydroxy-1-methylethyl)-N-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide(5b): Butyryl chloride (258 μL, 2.5 mmol) was added to a solution ofintermediate (5a) (1.1 g, 2.1 mmol), and DIPEA (504 μL, 2.9 mmol) intoluene (20 mL) at 0° C. The solution was stirred at room temperaturefor 30 minutes. Water was added (20 mL), and the aqueous phase wasextracted with EtOAc (3×30 mL). The combined organic extracts werewashed with saturated aqueous NaCl, dried over MgSO₄, filtered, andconcentrated in vacuo. Silica gel chromatography gave intermediate (5b)as a white solid (942 mg).

N—((S)-1-Methyl-2-oxoethyl)-N-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide(5c): Dess-Martin periodinane (971 mg, 2.3 mmol) was added to a solutionof intermediate (5b) (474 mg, 0.8 mmol) in DCM (20 mL) at roomtemperature. After 30 minutes, water (20 mL) and saturated aqueoussodium thiosulfate (20 mL) was added. The mixture was extracted with DCM(3×30 mL), washed with saturated aqueous NaCl (20 mL), dried over MgSO₄,and concentrated in vacuo. Silica gel chromatography gave intermediate(5c) as a white solid (411 mg).

N—((S)-2-Hydroxyimino-1-methylethyl)-N-[2′-(1-trityl-1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]butyramide(5d): Hydroxylamine hydrochloride (25.4 mg, 0.4 mmol) was added to asolution of intermediate (5c) (174 mg, 0.3 mmol), pyridine (3 mL, 37mmol) and water (1.5 mL, 83 mmol) at room temperature. After 15 minutes,water (10 mL) was added and the mixture was extracted with EtOAc (3×20mL). The combined organic extracts were washed with saturated aqueousNaCl (10 mL), dried over MgSO₄, filtered, and concentrated in vacuo.Silica gel chromatography gave intermediate (5d) as a white solid (148mg).

N—((S)-2-Amino-1-methylethyl)-N-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide(5e): A solution of intermediate (5d) (105 mg, 0.2 mmol), sodiumcyanoborohydride (47 mg, 0.7 mmol), ammonium acetate (28 mg, 0.4 mmol),and MeOH (6.0 mL) was cooled to 0° C. After 15 minutes, titanium (H)chloride (83 mg, 0.5 mmol) was added. After 10 minutes, ammoniumhydroxide (1 mL) was added and the mixture was stirred at roomtemperature for 5 minutes. The mixture was filtered through Celite®,rinsing with MeOH, and the filtrate was concentrated in vacuo to yield awhite solid. The solid was extracted with DCM and water. The combinedorganic extracts were washed with saturated aqueous NaCl, dried overMgSO₄, filtered, and concentrated in vacuo to afford intermediate (5e)(95 mg), which was used directly in the next step.

Thioacetic acidS—[2-((S)-2-butyryl-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminopropylcarbamoyl)-4-methylpentyl]ester(5f): BOP (74.4 mg, 0.2 mmol), followed by DIPEA (40.0 μL, 0.2 mmol) wasadded to a solution of intermediate (5e) (95 mg, 0.2 mmol),2-acetylsulfanylmethyl-4-methyl-pentanoic acid (34.4 mg, 0.2 mmol) andDMF (4.0 mL, 51 mmol) at room temperature. After 20 minutes, the mixturewas concentrated in vacuo. Silica gel chromatography gave intermediate(5f) as a colorless oil (67 mg).

Title compound (5-1): A solution of intermediate (5f) (34 mg, 42 μmol),MeOH (1.0 mL), and 1.0 M aqueous HCl (0.3 mL) was stirred under anatmosphere of nitrogen at room temperature. After 30 minutes, 1M aqueousNaOH (1.3 mL), and 6M aqueous NaOH (0.2 mL) was added. After 90 minutes,the mixture was neutralized with 6.0 N HCl and concentrated in vacuo.Reverse phase HPLC gave compound (5-1) as a white solid (7.8 mg). MSm/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S, 523.28. found 523.4.

2-Mercaptomethyl-4-methylpentanoic acid((S)-2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}-3-methylbutyl)amide(5-2) was made in a similar manner.

MS m/z: [M+H⁺] calcd for C₃₀H₄₂N₆O₂S, 551.31. found 551.4.

Example 6 Thioacetic AcidS-[3-methyl-1-(2-{pentanoyl-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amino}ethylcarbamoyl)butyl]ester(6-1; R⁵=—S—C(O)—CH₃) and 2-Mercapto-4-methylpentanoic Acid(2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide(6-2; R⁵=—SH)

(2-[2′-(1-Trityl-1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]aminoethyl)carbamicacid t-butyl ester (6a): A solution of5-(4′-bromomethylbiphenyl-2-yl)-1-trityl-1H-tetrazole (20.9 g, 37.4mmol) made as described in Preparation 1, N-(2-aminoethyl)(t-butoxy)carboxamide (15 g, 93.6 mmol), and potassium carbonate (15.5 g, 112mmol) in THF (75 mL) was stirred at room temperature for 48 hours. Themixture was concentrated and extracted with 1M aqueous KOH (20 mL) andEtOAc (2×200 mL). The combined organic extracts were dried over Na₂SO₄,filtered, and concentrated in vacuo. Intermediate (6a) was used withoutfurther purification.

(2-Pentanoyl-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl)carbamic acid t-butyl ester (6b) and pentanoic acid(2-aminoethyl)-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide (6c):Valeryl chloride (1.4 mL, 11.9 mmol) was added to a solution ofintermediate (6a) (6.9 g, 10.8 mmol) in toluene (70 mL) at 0° C.followed by DIPEA (3.8 mL, 21.6 mmol). After 3 hours at roomtemperature, 1M aqueous NaOH (5 mL) was added and the solvent wasremoved in vacuo. The concentrate was extracted with EtOAc and water.The combined organic fractions were dried over Na₂SO₄, filtered, andconcentrated in vacuo to afford intermediate (6b). A solution ofintermediate (6b) in 1,4-dioxane (30 mL) and 4M HCl (30 mL), and wasstirred at room temperature for 1 hour. The precipitate was filtered andpurified by reverse phase HPLC to afford (6c) as a TFA salt.

Title compounds (6-1) and (6-2): A solution of HATU (127 mg, 0.3 mmol),α-bromoisocaproic acid (51.3 μL, 340 μmol), and DIPEA (53 μL) wasdissolved in DMF (2.5 mL) at room temperature. After 15 minutes, asolution of intermediate (6c) (150 mg) and DIPEA (53 μL, 1 eq) in DMF(2.5 mL) was added. After 10 minutes, potassium thioacetate (243 mg, 2.1mmol) was added. After 20 minutes, water (5 mL) was added and themixture was extracted with EtOAc (3×15 mL), washed with saturatedaqueous NaCl (2×5 mL), dried over Na₂SO₄, filtered and concentrated invacuo. Reverse phase HPLC gave the title compound (6-1). Compound (6-1)was dissolved in MeOH (4 mL), 1N NaOH (4 mL), and 6N NaOH (0.2 mL),under an atmosphere of nitrogen. After 90 minutes, the mixture wasneutralized with 6M aqueous HCl, and was concentrated in vacuo. Reversephase HPLC gave title compound (6-2) (50.8 mg).

(6-1) MS m/z: [M+H⁺] calcd for C₂₉H₃₈N₆O₃S, 551.27. found 551.2. and

(6-2) MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.5.

Preparation 3 3-Methylpentanoyl Chloride

Thionyl chloride (4.7 mL, 64.6 mmol) was added to a solution of3-methylpentanoic acid (2.5 g, 21.5 mmol) in DCM (10 mL) at roomtemperature. After stirring overnight, the solvent was removed in vacuoto afford the crude title compound as a colorless oil (2.7 g).

Preparation 4 Cyclopropylacetyl Chloride

Thionyl chloride (1.1 mL, 15 mmol) was added to a solution ofcyclopropylacetic acid (0.5 g, 5 mmol) in DCM (2.3 mL, 35.1 mmol). Themixture was stirred at room temperature overnight, then concentrated toafford the crude title compound (0.4 g).

Preparation 5 4-Methylpentanoyl Chloride

Thionyl chloride (4.8 mL, 66.4 mmol) was added to a solution ofisocaproic acid (2.6 g, 22.1 mmol) in DCM (10 mL, 156 mmol) at roomtemperature and was stirred overnight. Thionyl chloride was removed invacuo to give the crude title compound (2.9 g) as a colorless oil.

Example 7 2-Mercaptomethyl-4-methylpentanoic Acid(2-{(3-Methylpentanoyl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide(7-1; R³=—CH—CH(CH)CH₇CH₃), 2-Mercaptomethyl-4-methylpentanoic Acid(2-{(2-cyclopropylacetyl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide(7-2; R³=—CH₂-cyclopropyl), 2-Mercaptomethyl-4-methylpentanoic Acid(2-{(4-Methylpentanoyl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide(7-3; R³=—(CH₂)₂—CH(CH₃)₂) and 2-Mercaptomethyl-4-methylpentanoic Acid(2-{(3-Methylbutyryl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide(7-4; R³=—CH₂—CH(CH₃)₂)

(2-[2′-(1-Trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethyl)carbamicacid t-butyl ester (7a): A solution of5-(4′-bromomethylbiphenyl-2-yl)-1-trityl-1H-tetrazole made as describedin Preparation 1 (20.9 g, 40 mmol), N-(2-aminoethyl)(t-butoxy)carboxamide (15 g, 90 mmol), and potassium carbonate (15.5 g, 110 mmol)in THF (75 mL) was stirred for 48 hours at room temperature. The mixturewas concentrated and extracted with 1M aqueous KOH (20 mL) and EtOAc(2×200 mL). The combined organic extracts were dried over Na₂SO₄,filtered, and concentrated. Silica gel chromatography (EtOAc:hexanes)gave intermediate (7a) as a white solid (12.7 g).

(2-{Benzyloxycarbonyl-[2′-(1-trityl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)carbamicacid t-butyl ester (7b): Intermediate (7a) (3.3 g, 5.2 mmol) wasdissolved in DCM and cooled to 0° C. DIPEA (2.7 mL, 15.6 mmol) wasadded, followed by benzyl chloroformate (804 μL, 5.7 mmol). After 90minutes, water (20 mL) was added and the mixture was extracted DCM (3×80mL) then washed with saturated aqueous NaCl. The combined organicextracts were dried over MgSO₄, filtered, and concentrated in vacuo toafford intermediate (7b) as a white solid (4.6 g).

(2-Aminoethyl)-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic acidbenzyl ester as the TFA salt (7c): A solution of intermediate (7b),1,4-dioxane (46 mL), and 4M HCl in 1,4-dioxane (46 mL) was stirred atroom temperature. After 2 hours, the solvent was removed in vacuo.Reverse phase HPLC gave intermediate (7c) (2.1 g).

Thioacetic acidS-[2-(2-benzyloxycarbonyl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]aminoethylcarbamoyl)-4-methylpentyl]ester(7d): A solution of intermediate (7c) (2.1 g) in DMF (10 mL) was addedto a solution of 2-acetylsulfanylmethyl-4-methylpentanoic acid (1 g, 5mmol) and DIPEA (1.2 mL, 6.9 mmol) in DMF (20 mL) at room temperature.BOP (2.2 g, 5.1 mmol) was added, followed by DIPEA (1.2 mL, 6.9 mmol).After 2 hours, the solvent was removed in vacuo. Silica gelchromatography gave intermediate (7d) (953 mg).

Thioacetic acidS-[4-methyl-2-(2-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]aminoethylcarbamoyl)pentyl]esteras the TFA salt (7e): Iodotrimethylsilane (2 mL, 14 mmol) was added to asolution of intermediate (7d) (2.2 g, 3.5 mmol) in DCM (35 mL) at roomtemperature under an atmosphere of nitrogen. After stirring overnight,the solvent was removed in vacuo. Reverse phase HPLC gave intermediate(7e) as a white solid (1.7 g).

Title compounds (7-1), (7-2), (7-3) and (7-4): In 4 separate vials,intermediate (7e) (60 mg, 101 μmol) was dissolved in THF (1 mL, 12.3mmol). Into each mixture was added 3-methylpentanoyl chloride (15.2 μL,111 μmol) made as described in Preparation 3, or cyclopropylacetylchloride (12.4 μL, 111 μmol) made as described in Preparation 4,4-methylpentanoyl chloride (15.2 μL, 111 μmol) made as described inPreparation 5, or isovaleryl chloride (13.5 μL, 111 μmol). Into eachmixture was added DIPEA (52.7 μL, 0.3 mmol) at room temperature. After 2hours, to each mixture was added 0.33 eq of the respective acidchloride. After 15 minutes, the solvent was removed in vacuo. Each crudemixture was dissolved in MeOH (1 mL), 1M aqueous NaOH (1 mL), and 6Maqueous NaOH (0.2 mL) under an atmosphere of nitrogen at roomtemperature. After 90 minutes, each mixture was neutralized with 6Maqueous HCl, and concentrated in vacuo. Reverse phase HPLC gave thetitle compounds:

(7-1) 20.1 mg, 100% purity; MS m/z: [M+H⁺] calcd for C₂₉H₄₀N₆O₂S,537.29. found 537.4.

(7-2) 21.3 mg, 99% purity; MS m/z: [M+H⁺] calcd for C₂₈H₃₆N₆O₂S, 521.26.found 521.2.

(7-3) 24.0 mg, 100% purity; MS m/z: [M+H⁺] calcd for C₂₉H₄₀N₆O₂S,537.29. found 537.4. and

(7-4) 24.4 mg, 100% purity; MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S,523.28. found 523.2.

Preparation 6 4′-Formylbiphenyl-2-sulfonic Acid t-Butylamide

2-Bromo-N-t-butylbenzenesulfonamide (6a): t-Butylamine (10 mL, 98 mmol),followed by DIPEA (19 mL, 110 mmol) was added to a solution of2-bromobenzenesulfonyl chloride (25 g, 98 mmol) in DCM (210 mL) at 0° C.The mixture was allowed to warm to room temperature and was stirredovernight. The mixture was then extracted with 1M aqueous HCl (2×80 mL),followed by saturated aqueous NaHCO₃ (80 mL) and saturated aqueous NaCl(80 mL). The organic phase was dried over Na₂SO₄, filtered, andconcentrated in vacuo. Crystallization from EtOAc and hexane affordedintermediate (6a) (21.5 g). MS m/z: [M+H⁺] calcd 292.19. found 292.0.

A solution of intermediate (6a) (10 g, 30 mmol), 4-formylphenylboronicacid (6.2 g, 41 mmol), tetrakis(triphenylphosphine)palladium(0) (2 g, 2mmol), potassium carbonate (9.5 g, 68.4 mmol), water (30 mL), EtOH (74mL), and toluene (150 mL) was stirred overnight at 80° C. undernitrogen. The mixture was then concentrated in vacuo. The concentratewas extracted with EtOAc (3×200 mL) and 1M aqueous HCl (150 mL). Thecombined organic extracts were dried over Na₂SO₄, filtered, andconcentrated in vacuo. The crude material was crystallized from EtOAcand hexane to afford the title compound (7.5 g).

Preparation 7 (S)-3-Acetylsulfanyl-2-benzylpropionic Acid

3-Phenylpropionyl chloride (7a): Thionyl chloride (21.8 mL, 300 mmol)was added to a solution of 3-phenylpropionic acid (15 g, 99.9 mol) inDCM (40 mL) and was stirred overnight. The mixture was concentrated invacuo to yield intermediate (7a), which was used in the next stepwithout further purification.

(S)-4-Benzyl-3-(3-phenylpropionyl)oxazolidin-2-one (7b): 1.6 M ofn-Butyllithium in hexanes (35 mL) was added to a solution of(S)-4-benzyloxazolidin-2-one (10 g, 56.4 mmol) in THF (150 mL) at −78°C. After 15 minutes, intermediate (7a) (9.5 g, 56.4 mmol) in THF (20 mL)was added dropwise at −78° C. After 30 minutes, the mixture was allowedto warm to room temperature and was stirred overnight. The mixture wasconcentrated in vacuo and the crude material was extracted with EtOAc(3×200 mL) and water (100 mL). The combined organic extracts were driedover Na₂SO₄, filtered, and concentrated in vacuo to yield intermediate(7b), which was used in the next step without further purification.

(S)-4-Benzyl-3-((R)-2-hydroxymethyl-3-phenylpropionyl)-oxazolidin-2-one(7c): 1 M of titanium tetrachloride in DCM (43 mL) was added to asolution of intermediate (7b) (12.7 g, 41 mmol) in DCM (150 mL) at 0° C.under nitrogen. After 20 minutes, DIPEA (7.9 mL, 45.2 mmol) was addeddropwise at 0° C. After 80 minutes, 1,3,5-trioxane (4.1 g, 45.2 mmol) inDCM (30 mL) was added, followed by a second equivalent of 1 M titaniumtetrachloride in DCM after 10 minutes. After 2.5 hours at 0° C., themixture was quenched with saturated aqueous NH₄Cl (150 mL). The productwas extracted with water (100 mL) and DCM (3×200 mL). The combinedorganic extracts were dried over Na₂SO₄, filtered, and concentrated invacuo to yield intermediate (7c), which was used in the next stepwithout further purification.

(R)-2-Hydroxymethyl-3-phenylpropionic acid (7d): 9 M of Hydrogenperoxide in water (50 mL) was added to a solution of intermediate (7c)(14.8 g, 43.6 mmol) in THF (100 mL) at 0° C. followed by the addition ofaqueous 1.5 M lithium hydroxide monohydrate (58 mL). After 2.5 hours atroom temperature, sodium sulfite (10 g) in water (100 mL) was added andthe mixture was stirred for 30 minutes. The mixture was extracted withwater (300 mL) and chloroform (2×150 mL). The aqueous layer wasacidified to pH2 with aqueous 6M HCl and extracted with EtOAc (3×200mL). The combined organic extracts were dried over Na₂SO₄, filtered, andconcentrated in vacuo to yield intermediate (7d), which was used in thenext step without further purification.

Diisopropyl azodicarboxylate (14.8 mL, 75.2 mmol) was added to asolution of triphenylphosphine (19.7 g, 75.2 mmol) and THF (100 mL) at0° C. After 10 minutes, a solution of thioacetic acid (8.1 mL, 113 mmol)and intermediate (7d) (6.8 g, 37.6 mmol) in THF (15 mL) was addeddropwise to the mixture at 0° C. After 3.5 hours at room temperature,the mixture was concentrated and then extracted with saturated aqueousNaHCO₃ (2×200 mL) and EtOAc (150 mL). The aqueous layer was combined andacidified to pH2 with 6M aqueous HCl, then extracted with EtOAc (3×200mL). The organic layer was dried over Na₂SO₄, filtered, and concentratedin vacuo. Silica gel chromatography (hexane:EtOAc (5% AcOH)) affordedthe title compound (3.6 g).

Example 8 Pentanoic acid(2′-acetylsulfamoylbiphenyl-4-ylmethyl)-[2-((S)-2-benzyl-3-mercaptopropionylamino)ethyl]amide

{2-[(2′-t-Butylsulfamoylbiphenyl-4-ylmethyl)amino]ethyl}carbamic acidt-butyl ester.C₂HF₃O₂ (8a): 4′-Formylbiphenyl-2-sulfonic acidt-butylamide (5.8 g, 18 mmol; prepared as described in Preparation 6)was added to a solution of N-(2 -aminoethyl)(t-butoxy)carboxamide (2.7g, 16.6 mmol) in 1% AcOH in MeOH (40 mL), followed by the addition ofsodium cyanoborohydride (1.2 g, 18.3 mmol). The mixture was concentratedin vacuo. Reverse phase HPLC afforded intermediate (8a) as a TFA salt(5.6 g). MS m/z: [M+H⁺] calcd 461.62. found 462.3.

Pentanoic acid(2-aminoethyl)-(2′-sulfamoylbiphenyl-4-ylmethyl)amide.C₂HF₃O₂ (8b):Valeryl chloride (394 μL, 3.3 mmol) was added to a solution ofintermediate (8a) (1.8 g) and DIPEA (1.7 mL, 9.6 mmol) in toluene (9 mL)at 0° C. After stirring overnight, the mixture was concentrated in vacuoand extracted with EtOAc (2×100 mL) and 1M aqueous HCl (50 mL). Thecombined organic extracts were dried over Na₂SO₄, filtered, andconcentrated in vacuo to afford the crude intermediate (8b). A solutionof (8b) in DCM (5 mL) and TFA (12 mL) was heated at 40° C. After 8hours, the mixture was concentrated in vacuo. Reverse phase HPLCafforded intermediate (8b) as a TFA salt (1.1 g). MS m/z: [M+H⁺] calcd389.51. found 390.4.

Thioacetic acidS—((S)-2-{2-[pentanoyl-(2′-sulfamoylbiphenyl-4-ylmethyl)amino]ethylcarbamoyl}-3-phenylpropyl)ester (8c): A solution of (S)-3-acetylsulfanyl-2-benzylpropionic acid(248 mg, 1 mmol; prepared as described in Preparation 7) and HATU (396mg, 1 mmol) in DMF (2.5 mL) was prepared. After 30 minutes, intermediate(8b) (500 mg) followed by DIPEA (0.5 mL, 3 mmol) was added. After 2hours, the mixture was concentrated in vacuo. Silica gel chromatography[hexane:EtOAc (5% AcOH)] afforded intermediate (8c) (636 mg). MS m/z:[M+H⁺] calcd 609.80. found 610.4.

Title compound: Acetyl chloride (222 μL, 3.1 mmol), followed by DIPEA(727 μL, 4.3 mmol) was added to a solution of intermediate (8c) (636 mg,1 mmol) in DCM (3 mL). After stirring overnight, the mixture wasextracted with 0.5M aqueous HCl (15 mL) and DCM (2×20 mL). The combinedorganic fractions were dried over Na₂SO₄, filtered, and concentrated invacuo to afford a crude intermediate. A solution of the crudeintermediate in MeOH (2 mL) and 1M aqueous NaOH (1 mL) was stirred undernitrogen for 1 hour. The mixture was neutralized with 6M aqueous HCl andconcentrated in vacuo. Reverse phase HPLC afforded the title compound(63.7 mg). MS m/z: [M+H⁺] calcd for C₃₂H₃₉N₃O₅S₂ 610.23. found 610.5.

Example 9

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 9-1 to 9-15,having the following formula, were also prepared:

Ex. R⁵ R⁶ 9-1 —CH₂—SH —(CH₂)₂CH(CH₃)₂ 9-2 —CH₂—SH —(CH₂)₃CH₃ 9-3 —CH₂—SH—CH(CH₃)CH₂CH₃ 9-4 —CH₂—SH —CH₂-cyclopentyl 9-5 —CH₂—SH —CH₂-cyclohexyl9-6 —CH₂—SH —CH₂-naphthalen-1-yl 9-7 —SH —CH₂CH(CH₃)₂ 9-8 —SH—CH₂CH(CH₃)₂ 9-9 —SH —(CH₂)₂CH₃ 9-10 —SH —(CH₂)₂CH₃ 9-11 —CH₂—SH—CH₂-cyclopropyl 9-12 —CH₂—SH -cyclohexyl 9-13 —SH —CH₂C(CH₃)₃ 9-14 —SH—CH₂C(CH₃)₃ 9-15 —CH₂—SH -benzyl

-   (9-1) 2-mercaptomethyl-5-methylhexanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S, 523.28. found 523.2.-   (9-2) 2-mercaptomethylhexanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.2.-   (9-3) 2-mercaptomethyl-3-methylpentanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.2.-   (9-4)    N-[2-(3-cyclopentyl-2-mercaptomethylpropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₈N₆O₂S, 535.28. found 535.2.-   (9-5)    N-[2-(3-cyclohexyl-2-mercaptomethylpropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₃₀H₄₀N₆O₂S, 549.29. found 549.2.-   (9-6)    N-[2-(2-mercaptomethyl-3-naphthalen-1-ylpropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)-biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₃₄H₃₆N₆O₂S, 593.26. found 593.2.-   (9-7) (R)-2-mercapto-4-methylpentanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₂S, 495.25. found 495.2.-   (9-8) (S)-2-mercapto-4-methylpentanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₂S, 495.25. found 495.2.-   (9-9) (R)-2-mercaptopentanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₅H₃₂N₆O₂S, 481.23. found 480.6.-   (9-10) (S)-2-mercaptopentanoic acid    (2-{butyryl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₅H₃₂N₆O₂S, 481.23. found 481.2.-   (9-11)    N-[2-(2-cyclopropylmethyl-3-mercaptopropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₄N₆O₂S, 507.25. found 507.2.-   (9-12)    N-[2-(2-cyclohexyl-3-mercaptopropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₈N₆O₂S, 535.28.-   (9-13) (S)-2-mercapto-4,4-dimethylpentanoic acid    (2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.2.-   (9-14) (R)-2-mercapto-4,4-dimethylpentanoic acid    (2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.2.-   (9-15)    N-[2-((S)-2-benzyl-3-mercaptopropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₄N₆O₂S, 543.25. found 543.4.

Example 10

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 10-1 and10-2, having the following formula, were also prepared:

-   (10-1)    4-({[2-(2-hydroxycarbamoyl-4-methylpentanoylamino)ethyl]pentanoylamino}methyl)benzoic    acid (R⁶=i-butyl). MS m/z: [M+H⁺] calcd for C₂₂H₃₃N₃O₆, 436.24.    found 436.2.-   (10-2)    4-({[2-(2-hydroxycarbamoyl-3-phenylpropionylamino)ethyl]pentanoylamino}methyl)benzoic    acid (R⁶=benzyl). MS m/z/z: [M+H⁺] calcd for C₂₅H₃₁N₃O₆, 470.22.    found 470.2.

Example 11

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 11-1 to11-10, having the following formula, were also prepared:

Ex. R⁵ R⁶ 11-1 —CH₂—SH —CH₂CH(CH₃)₂ 11-2 —CH₂—SH benzyl 11-3 —CH₂—SH—CH(CH₃)₂ 11-4 —SH —CH(CH₃)CH₂CH₃ 11-5 —CH₂—SH —CH₃ 11-6 —NHC(O)CH₂SH—CH₂CH(CH₃)₂ 11-7 —C(O)NH(OH) benzyl 11-8 —CH₂—SH —CH₂CH(CH₃)₂ 11-9—CH₂—SH —CH₂CH(CH₃)₂ 11-10 —CH₂—SH benzyl

-   (11-1) 2-mercaptomethyl-4-methylpentanoic acid    (2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S, 523.28. found 523.4.-   (11-2) pentanoic acid    [2-(2-benzyl-3-mercaptopropionylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₃₁H₃₆N₆O₂S, 557.26. found 557.4.-   (11-3) pentanoic acid    [2-(2-mercaptomethyl-3-methylbutyrylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.4.-   (11-4) 2-mercapto-3-methylpentanoic acid    (2-{pentanoyl[2′-(H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.4.-   (11-5) pentanoic acid    [2-((S)-3-mercapto-2-methylpropionylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₅H₃₂N₆O₂S, 481.23. found 481.2.-   (11-6) (S)-2-(2-mercaptoacetylamino)-4-methylpentanoic acid    (2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₉N₇O₃S, 566.28. found 566.4.-   (11-7)    2-benzyl-N-hydroxy-N′-(2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)malonamide.    MS m/z: [M+H⁺] calcd for C₃₁H₃₅N₇O₄, 570.28. found 570.4.-   (11-8) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S, 523.28. found 523.2.-   (11-9) (R)-2-mercaptomethyl-4-methylpentanoic acid    (2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S, 523.28. found 523.3.-   (11-10) pentanoic acid    [2-((R)-2-benzyl-3-mercaptopropionylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₃₁H₃₆N₆O₂S, 557.26. found 557.2.

Example 12

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 12-1 and12-2, having the following formula, were also prepared:

-   (12-1) pentanoic acid    [(S)-1-((R)-1-benzyl-2-mercaptoethylcarbamoyl)-2-methylpropyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide    (R⁶=benzyl). MS m/z: [M+H⁺] calcd for C₃₃H₄₀N₆O₂S, 585.29. found    585.5.-   (12-2) pentanoic acid    [(S)-1-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)-2-methylpropyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide    (R⁶=—CH₂CH(CH₃)₂). MS m/z: [M+H⁺] calcd for C₃₀H₄₂N₆O₂S, 551.31.    found 551.4.

Example 13

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 13-1 to13-17, having the following formula, were also prepared:

Ex. R¹ R³ R⁵ R⁶ 13-1 tetrazol-5-yl —(CH₂)₂CH₃ —CH₂—SH benzyl 13-2tetrazol-5-yl —(CH₂)₂CH₃ —C(O)NH(OH) —CH₂CH(CH₃)₂ 13-3 tetrazol-5-yl—(CH₂)₂CH₃ —C(O)NH(OH) benzyl 13-4 tetrazol-5-yl —(CH₂)₂CH₃ —CH₂—SH—CH(CH₃)₂ 13-5 tetrazol-5-yl —CH₃ —C(O)NH(OH) benzyl 13-6 tetrazol-5-yl—CH₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 13-7 tetrazol-5-yl —CH₂CH₃ —CH₂—SH benzyl13-8 tetrazol-5-yl —CH₂CH₃ —CH₂—SH —CH₃ 13-9 tetrazol-5-yl —CH₂CH₃—CH₂—SH —CH₂-cyclopropyl 13-10 tetrazol-5-yl —CH₂CH₃ —SH benzyl 13-11tetrazol-5-yl —CH₂CH₃ —C(O)NH(OH) —CH₂CH(CH₃)₂ 13-12 tetrazol-5-yl—CH₂CH₃ —C(O)NH(OH) benzyl 13-13 tetrazol-5-yl —CH₂CH₃ —CH₂—SH —CH₃13-14 tetrazol-5-yl —(CH₂)₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 13-15 tetrazol-5-yl—(CH₂)₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 13-16 tetrazol-5-yl —CH(CH₂CH₃)₂ —CH₂—SH—CH₂CH(CH₃)₂ 13-17 —SO₂NHC(O)CH₃ —(CH₂)₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂

-   (13-1)    N-[2-(2-mercaptomethyl-3-phenylpropionylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₄N₆O₂S, 543.25. found 543.2.-   (13-2)    N-(2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)-N′-hydroxy-2-isobutylmalonamide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₅N₇O₄, 522.28. found 522.2.-   (13-3)    2-benzyl-N-(2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)-N′-hydroxymalonamide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₃N₇O₄, 556.26. found 556.2.-   (13-4)    N-(2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)-2-mercaptomethyl-3-methylbutyramide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₂S, 495.25. found 495.2.-   (13-5)    N-(2-{acetyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)-2-benzyl-N′-hydroxymalonamide.    MS m/z: [M+H⁺] calcd for C₂₈H₂₉N₇O₄, 528.23. found 528.2.-   (13-6) 2-mercaptomethyl-4-methylpentanoic acid    (2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₂S, 495.25. found 495.0.-   (13-7)    2-mercaptomethyl-3-phenyl-N-(2-{propionyl-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)propionamide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₂N₆O₂S, 529.23. found 529.0.-   (13-8)    3-mercapto-2-methyl-N-(2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)propionamide.    MS m/z: [M+H⁺] calcd for C₂₃H₂₈N₆O₂S, 453.20. found 453.0.-   (13-9)    3-cyclopropyl-2-mercaptomethyl-N-(2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)propionamide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₂N₆O₂S, 493.23. found 493.0.-   (13-10)    (S)-2-mercapto-3-phenyl-N-(2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)propionamide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₀N₆O₂S, 515.22. found 515.0.-   (13-11)    N-hydroxy-2-isobutyl-N′-(2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)malonamide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₃N₇O₄, 508.26. found 508.0.-   (13-12)    2-benzyl-N-hydroxy-N′-(2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)malonamide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₁N₇O₄, 542.24. found 542.0.-   (13-13)    (S)-3-mercapto-2-methyl-N-(2-{propionyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)propionamide.    MS m/z: [M+H⁺] calcd for C₂₃H₂₈N₆O₂S, 453.20. found 453.0.-   (13-14) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.2.-   (13-15) (R)-2-mercaptomethyl-4-methylpentanoic acid    (2-{butyryl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₂S, 509.26. found 509.2.-   (13-16) 2-mercaptomethyl-4-methylpentanoic acid    (2-{(2-ethylbutyryl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₉H₄₀N₆O₂S, 537.29. found 537.4.-   (13-17) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoylbiphenyl-4-ylmethyl)butyrylamino]ethyl}amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₉N₃O₅S₂, 562.23. found 562.5.

Example 14

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 14-1 to 14-7,having the following formula, were also prepared:

Ex. X R⁵ R⁶ 14-1

—CH₂—SH benzyl 14-2 —CH₂—C(O)NH— —CH₂NHC(O)—CH₂SH —CH(CH₃)₂ 14-3—CH₂—C(O)NH— —CH₂—SH benzyl 14-4 —CH₂—C(O)NH— —C(O)NH(OH) —CH₂CH(CH₃)₂14-5 —CH₂—C(O)NH— —C(O)NH(OH) —CH₂CH(CH₃)₂ 14-6 —CH₂—C(O)NH——CH₂C(O)NH(OH) benzyl 14-7 —CH₂—C(O)NH— —CH₂C(O)NH(OH) benzyl

-   (14-1)    4′-{[((S)-1-{2-[2-(2-benzyl-3-mercaptopropionylamino)acetylamino]ethylcarbamoyl}-2-methylpropyl)pentanoylamino]methyl}biphenyl-2-carboxylic    acid. MS m/z: [M+H⁺] calcd for C₃₈H₄₈N₄O₆S, 689.33.-   (14-2)    4′-{[({(R)-1-[(2-mercaptoacetylamino)methyl]-2-methylpropylcarbamoyl}methyl)pentanoylamino]methyl}biphenyl-2-carboxylic    acid. MS m/z: [M+H⁺] calcd for C₂₈H₃₇N₃O₅S, 528.25. found 528.4.-   (14-3)    4′-({[((R)-1-benzyl-2-mercaptoethylcarbamoyl)methyl]pentanoylamino}methyl)biphenyl-2-carboxylic    acid. MS m/z: [M+H⁺] calcd for C₃₀H₃₄N₂O₄S, 519.22. found 519.4.-   (14-4)    4′-({[((S)-1-hydroxycarbamoyl-3-methylbutylcarbamoyl)methyl]pentanoylamino}methyl)biphenyl-2-carboxylic    acid. MS m/z: [M+H⁺] calcd for C₂₇H₃₅N₃O₆, 498.25. found 498.4.

(14-5)4′-({[((S)-1-hydroxycarbamoyl-2-phenylethylcarbamoyl)methyl]pentanoylamino}methyl)biphenyl-2-carboxylicacid. MS m/z: [M+H⁺] calcd for C₃₀H₃₃N₃O₆, 532.24. found 532.4.

-   (14-6)    4′-({[(1-hydroxycarbamoylmethyl-3-methylbutylcarbamoyl)methyl]pentanoylamino}methyl)biphenyl-2-carboxylic    acid. MS m/z: [M+H⁺] calcd for C₂₈H₃₇N₃O₆, 512.27. found 512.4.-   (14-7)    4′-({[(1-benzyl-2-hydroxycarbamoylethylcarbamoyl)methyl]pentanoylamino}methyl)biphenyl-2-carboxylic    acid. MS m/z: [M+H⁺] calcd for C₃₁H₃₅N₃O₆, 546.25. found 546.4.

Example 15

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 15-1 to 15-8,having the following formula, were also prepared:

Ex. R³ X R⁵ 15-1 —(CH₂)₃CH₃

—C(O)NH(OH) 15-2 —(CH₂)₃CH₃

—C(O)NH(OH) 15-3 —(CH₂)₃CH₃

—CH₂—SH 15-4 —(CH₂)₃CH₃

—C(O)NH(OH) 15-5 —(CH₂)₃CH₃

—C(O)NH(OH) 15-6 —(CH₂)₃CH₃

—C(O)NH(OH) 15-7 —(CH₂)₃CH₃

—CH₂C(O)NH(OH) 15-8 —(CH₂)₂CH₃

—CH₂—SH

-   (15-1)    2-benzyl-N-hydroxy-N′-{[6-((S)-3-methyl-2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}butyrylamino)hexylcarbamoyl]methyl}malonamide.    MS m/z: [M+H⁺] calcd for C₄₂H₅₅N₉O₆, 782.43. found 782.3.-   (15-2)    3-(2-hydroxycarbamoyl-3-phenylpropionylamino)-2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propionic    acid. MS m/z: [M+H⁺] calcd for C₃₂H₃₅N₇O₆, 614.27. found 614.4.-   (15-3)    3-[2-(2-benzyl-3-mercaptopropionylamino)acetylamino]-2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propionic    acid. MS m/z: [M+H⁺] calcd for C₃₄H₃₉N₇O₅S, 658.27. found 658.3.-   (15-4)    2-[2-(2-hydroxycarbamoyl-3-phenylpropionylamino)acetylamino]-3-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propionic    acid. MS m/z: [M+H⁺] calcd for C₃₄H₃₈N₈O₇, 671.29. found 671.2.-   (15-5)    3-[2-(2-hydroxycarbamoyl-3-phenylpropionylamino)acetylamino]-2-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propionic    acid. MS m/z: [M+H⁺] calcd for C₃₄H₃₈N₈O₇, 671.29. found 671.2.-   (15-6)    2-(2-hydroxycarbamoyl-3-phenylpropionylamino)-3-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propionic    acid. MS m/z: [M+H⁺] calcd for C₃₂H₃₅N₇O₆, 614.27. found 614.2.-   (15-7) pentanoic acid    [(S)-1-(1-benzyl-2-hydroxycarbamoylethylcarbamoyl)-2-methylpropyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₃₄H₄₁N₇O₄, 612.32. found 612.2.-   (15-8)    N-[2-((S)-2-benzyl-3-mercaptopropionylamino)-2-methylpropyl]-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]butyramide.    MS m/z: [M+H⁺] calcd for C₃₂H₃₈N₆O₂S, 571.28. found 571.2.

Example 16

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 16-1 to16-32, having the following formula, were also prepared:

Ex. R³ R⁵ R⁶ 16-1 -cyclopropyl —CH₂—SH benzyl 16-2 -cyclopropyl —CH₂—SH—CH₂CH(CH₃)₂ 16-3 -cyclopropyl —CH₂—SH —CH₃ 16-4 -cyclopropyl —CH₂—SH—CH(CH₃)₂ 16-5 -cyclopropyl —SH benzyl 16-6 -cyclopropyl —C(O)NH(OH)—CH₂CH(CH₃)₂ 16-7 -cyclopropyl —C(O)NH(OH) benzyl 16-8 -cyclopropyl—CH₂—SH —CH₃ 16-9 —CH₂-cyclopentyl —CH₂—SH —CH₂CH(CH₃)₂ 16-10—(CH₂)₂-cyclopentyl —CH₂—SH —CH₂CH(CH₃)₂ 16-11 phenyl —CH₂—SH—CH₂CH(CH₃)₂ 16-12 benzyl —CH₂—SH —CH₂CH(CH₃)₂ 16-13 —(CH₂)₂-phenyl—CH₂—SH —CH₂CH(CH₃)₂ 16-14 —NH(CH₂)₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 16-15—NHCH₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 16-16 —NH(CH₂)₃CH₃ —CH₂—SH —CH₂CH(CH₃)₂16-17 —NH(CH₂)₄CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 16-18 —NH(CH₂)₅CH₃ —CH₂—SH—CH₂CH(CH₃)₂ 16-19 —NHCH(CH₃)₂ —CH₂—SH —CH₂CH(CH₃)₂ 16-20—NHCH(CH₃)CH₂CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 16-21 cyclopentyl —CH₂—SH—CH₂CH(CH₃)₂ 16-22 —CH₂-cyclohexyl —CH₂—SH —CH₂CH(CH₃)₂ 16-23 phenyl—CH₂—SH —CH₂CH(CH₃)₂ 16-24 benzyl —CH₂—SH —CH₂CH(CH₃)₂ 16-25 —O(CH₂)₂CH₃—CH₂—SH —CH₂CH(CH₃)₂ 16-26 —OCH₃ —CH₂—SH —CH₂CH(CH₃)₂ 16-27 —OCH₂CH₃—CH₂—SH —CH₂CH(CH₃)₂ 16-28 —O(CH₂)₃CH₃ —CH₂—SH —CH₂CH(CH₃)₂ 16-29—OCH(CH₃)₂ —CH₂—SH —CH₂CH(CH₃)₂ 16-30 —OCH₂CH(CH₃)₂ —CH₂—SH —CH₂CH(CH₃)₂16-31 —O-phenyl —CH₂—SH —CH₂CH(CH₃)₂ 16-32 —O-benzyl —CH₂—SH—CH₂CH(CH₃)₂

-   (16-1) cyclopropanecarboxylic acid    [2-(2-benzyl-3-mercaptopropionylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₂N₆O₂S, 541.23. found 541.0.-   (16-2) cyclopropanecarboxylic acid    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₄N₆O₂S, 507.25. found 507.0.-   (16-3) cyclopropanecarboxylic acid    [2-(3-mercapto-2-methylpropionylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₄H₂₈N₆O₂S, 465.20. found 465.0.-   (16-4) cyclopropanecarboxylic acid    [2-(2-mercaptomethyl-3-methylbutyrylamino)ethyl]-2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₂N₆O₂S, 493.23. found 493.0.-   (16-5) cyclopropanecarboxylic acid    [2-((S)-2-mercapto-3-phenylpropionylamino)ethyl]-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₀N₆O₂S, 527.22. found 527.0.-   (16-6)    N-(2-{cyclopropanecarbonyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)-N′-hydroxy-2-isobutylmalonamide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₃N₇O₄, 520.26. found 520.0.-   (16-7)    2-benzyl-N-(2-{cyclopropanecarbonyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)-N′-hydroxymalonamide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₁N₇O₄, 554.24. found 554.0.-   (16-8) cyclopropanecarboxylic acid    [2-((S)-3-mercapto-2-methylpropionylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₄H₂₈N₆O₂S, 465.20. found 465.0.-   (16-9) 2-mercaptomethyl-4-methylpentanoic acid    (2-{(2-cyclopentylacetyl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₀H₄₀N₆O₂S, 549.29. found 549.4.-   (16-10) 2-mercaptomethyl-4-methylpentanoic acid    (2-{(3-cyclopentylpropionyl)[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₁H₄₂N₆O₂S, 563.31. found 563.4.-   (16-11)    N-[2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl]-N-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]benzamide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₄N₆O₂S, 543.25. found 543.2.-   (16-12) 2-mercaptomethyl-4-methylpentanoic acid    (2-{phenylacetyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₁H₃₆N₆O₂S, 557.26. found 557.2.-   (16-13) 2-mercaptomethyl-4-methylpentanoic acid    (2-{(3-phenylpropionyl)    [2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}ethyl)amide. MS m/z:    [M+H⁺] calcd for C₃₂H₃₈N₆O₂S, 571.28. found 571.2.-   (16-14) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-propyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₇N₇O₂S, 524.27. found 524.2.-   (16-15) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-ethyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₅N₇O₂S, 510.26. found 510.2.-   (16-16) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-butyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₉N₇O₂S, 538.29. found 538.4.-   (16-17) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-pentyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₉H₄₁N₇O₂S, 552.30. found 552.4.-   (16-18) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-hexyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₀H₄₃N₇O₂S, 566.32. found 566.4.-   (16-19) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-isopropyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₇H₃₇N₇O₂S, 524.27. found 524.2.-   (16-20) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-sec-butyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₉N₇O₂S, 538.29. found 538.2.-   (16-21) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-cyclopentyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₉N₇O₂S, 550.29. found 550.4.-   (16-22) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-cyclohexylmethyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₁H₄₃N₇O₂S, 578.32. found 578.4.-   (16-23) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-phenyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₀H₃₅N₇O₂S, 558.26. found 558.2.-   (16-24) 2-mercaptomethyl-4-methylpentanoic acid    (2-{3-benzyl-1-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]ureido}ethyl)amide.    MS m/z: [M+H⁺] calcd for C₃₁H₃₇N₇O₂S, 572.27. found 572.2.-   (16-25)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid propyl ester. MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₃S, 525.26.    found 525.2.-   (16-26)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid methyl ester. MS m/z: [M+H⁺] calcd for C₂₅H₃₂N₆O₃S, 497.23.    found 497.2.-   (16-27)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid ethyl ester. MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₃S, 511.24.    found 511.2.-   (16-28)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid butyl ester. MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₃S, 539.27.    found 539.2.-   (16-29)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid isopropyl ester. MS m/z: [M+H⁺] calcd for C₂₇H₃₆N₆O₃S, 525.26.    found 525.2.-   (16-30)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid isobutyl ester. MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₃S, 539.27.    found 539.2.-   (16-31)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid phenyl ester. MS m/z: [M+H⁺] calcd for C₃₀H₃₄N₆O₃S, 559.24.    found 559.2.-   (16-32)    [2-(2-mercaptomethyl-4-methylpentanoylamino)ethyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]carbamic    acid benzyl ester. MS m/z: [M+H⁺] calcd for C₃₁H₃₆N₆O₃S, 573.26.    found 573.2.

Example 17

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 17-1 to 17-8,having the following formula, were also prepared:

Ex. R⁵ R⁶ 17-1 —C(O)NH(OH) —CH₂CH(CH₃)₂ 17-2 —C(O)NH(OH) benzyl 17-3—CH₂—SH benzyl 17-4 —SH benzyl 17-5 —CH₂—SH —CH₂CH(CH₃)₂ 17-6 —CH₂—SH—CH(CH₃)₂ 17-7 —CH₂—SH —CH₃ 17-8 —CH₂—SH —CH₃

-   (17-1)    N-hydroxy-2-isobutyl-N′-(3-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propyl)malonamide.    MS m/z: [M+H⁺] calcd for C₂₉H₃₉N₇O₄, 550.31. found 550.4.-   (17-2)    2-benzyl-N-hydroxy-N′-(3-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propyl)malonamide.    MS m/z: [M+H⁺] calcd for C₃₂H₃₇N₇O₄, 584.29. found 584.4.-   (17-3) pentanoic acid [3-(2-mercaptomethyl-3    -phenylpropionylamino)propyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₃₂H₃₈N₆O₂S, 571.28. found 571.4.-   (17-4) pentanoic acid [3-((S)-2-mercapto-3    -phenylpropionylamino)propyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₃₁H₃₆N₆O₂S, 557.26. found 557.2.-   (17-5) 2-mercaptomethyl-4-methyl-pentanoic acid    (3-{pentanoyl[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amino}propyl)amide.    MS m/z: [M+H⁺] calcd for C₂₉H₄₀N₆O₂S, 537.29. found 537.4.-   (17-6) pentanoic acid    [3-(2-mercaptomethyl-3-methylbutyrylamino)propyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₈H₃₈N₆O₂S, 523.28. found 523.2.-   (17-7) pentanoic acid    [3-((S)-3-mercapto-2-methylpropionylamino)propyl][2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₂S, 495.25. found 495.2.-   (17-8) pentanoic acid    [3-(3-mercapto-2-methylpropionylamino)propyl]-[2′-(1H-tetrazol-5-yl)biphenyl-4-ylmethyl]amide.    MS m/z: [M+H⁺] calcd for C₂₆H₃₄N₆O₂S, 495.25. found 495.2.

Example 18

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 18-1 and18-2, having the following formula, were also prepared:

-   (18-1)    4′-{N′-[2-(2-mercaptomethyl-3-phenylpropionylamino)acetyl]-N-pentanoylhydrazinomethyl}biphenyl-2-carboxylic    acid (R⁵=—CH₂—SH). MS m/z: [M+H⁺] calcd for C₃₁H₃₅N₃O₅S, 562.23.    found 562.3.-   (18-2)    4′-{N′-[2-(2-hydroxycarbamoyl-3-phenylpropionylamino)acetyl]-N-pentanoylhydrazinomethyl}biphenyl-2-carboxylic    acid (R⁵=—C(O)NH(OH)). MS m/z: [M+H⁺] calcd for C₃₁H₃₄N₄O₇, 575.24.    found 575.3.

Example 19

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 19-1 to 19-27and 19-29 to 19-60, having the following formulas (19a), (19b), (19c),(19d), (19e), or (19f), can also be prepared. Compound 19-28 wassynthesized in a manner similar to that described in Example 8.

(19a)

(19b)

(19c)

(19d)

(19e)

(19f)

Ex. Formula R^(1d) R⁶ 19-1 19a —C(O)—CH(CH₃)OH -2-fluorobenzyl 19-2 19a—C(O)—CH(CH₃)OH -3-chlorobenzyl 19-3 19a —C(O)—CH(CH₃)OH benzyl 19-4 19a—C(O)—CH(CH₃)OH i-butyl 19-5 19a —C(O)—CH(CH₃)OH cyclohexyl 19-6 19a—C(O)CH₃ -2-fluorobenzyl 19-7 19a —C(O)CH₃ -3-chlorobenzyl 19-8 19a—C(O)CH₃ benzyl 19-9 19a —C(O)CH₃ i-butyl 19-10 19a —C(O)CH₃ cyclohexyl19-11 19b —C(O)—CH(CH₃)OH -2-fluorobenzyl 19-12 19b —C(O)—CH(CH₃)OH-3-chlorobenzyl 19-13 19b —C(O)—CH(CH₃)OH benzyl 19-14 19b—C(O)—CH(CH₃)OH i-butyl 19-15 19b —C(O)—CH(CH₃)OH cyclohexyl 19-16 19b—C(O)CH₃ -2-fluorobenzyl 19-17 19b —C(O)CH₃ -3-chlorobenzyl 19-18 19b—C(O)CH₃ benzyl 19-19 19b —C(O)CH₃ i-butyl 19-20 19b —C(O)CH₃ cyclohexyl19-21 19c —C(O)—CH(CH₃)OH -2-fluorobenzyl 19-22 19c —C(O)—CH(CH₃)OH-3-chlorobenzyl 19-23 19c —C(O)—CH(CH₃)OH benzyl 19-24 19c—C(O)—CH(CH₃)OH i-butyl 19-25 19c —C(O)—CH(CH₃)OH cyclohexyl 19-26 19c—C(O)CH₃ -2-fluorobenzyl 19-27 19c —C(O)CH₃ -3-chlorobenzyl 19-28 19c—C(O)CH₃ benzyl 19-29 19c —C(O)CH₃ i-butyl 19-30 19c —C(O)CH₃ cyclohexyl19-31 19d —C(O)—CH(CH₃)OH -2-fluorobenzyl 19-32 19d —C(O)—CH(CH₃)OH-3-chlorobenzyl 19-33 19d —C(O)—CH(CH₃)OH benzyl 19-34 19d—C(O)—CH(CH₃)OH i-butyl 19-35 19d —C(O)—CH(CH₃)OH cyclohexyl 19-36 19d—C(O)CH₃ -2-fluorobenzyl 19-37 19d —C(O)CH₃ -3-chlorobenzyl 19-38 19d—C(O)CH₃ benzyl 19-39 19d —C(O)CH₃ i-butyl 19-40 19d —C(O)CH₃ cyclohexyl19-41 19e —C(O)—CH(CH₃)OH -2-fluorobenzyl 19-42 19e —C(O)—CH(CH₃)OH-3-chlorobenzyl 19-43 19e —C(O)—CH(CH₃)OH benzyl 19-44 19e—C(O)—CH(CH₃)OH i-butyl 19-45 19e —C(O)—CH(CH₃)OH cyclohexyl 19-46 19e—C(O)CH₃ -2-fluorobenzyl 19-47 19e —C(O)CH₃ -3-chlorobenzyl 19-48 19e—C(O)CH₃ benzyl 19-49 19e —C(O)CH₃ i-butyl 19-50 19e —C(O)CH₃ cyclohexyl19-51 19f —C(O)—CH(CH₃)OH -2-fluorobenzyl 19-52 19f —C(O)—CH(CH₃)OH-3-chlorobenzyl 19-53 19f —C(O)—CH(CH₃)OH benzyl 19-54 19f—C(O)—CH(CH₃)OH i-butyl 19-55 19f —C(O)—CH(CH₃)OH cyclohexyl 19-56 19f—C(O)CH₃ -2-fluorobenzyl 19-57 19f —C(O)CH₃ -3-chlorobenzyl 19-58 19f—C(O)CH₃ benzyl 19-59 19f —C(O)CH₃ i-butyl 19-60 19f —C(O)CH₃ cyclohexyl

These compounds are named below. Although the nomenclature depicts onestereoisomer embodiment, it is understood that all stereoisomeric formsof these compounds are included in the invention.

-   (19-1) pentanoic acid    {2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-2) pentanoic acid    {2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-3) pentanoic acid    [2-((S)-2-benzyl-3-mercaptopropionylamino)ethyl][2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-4) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]pentanoylamino}ethyl)amide;-   (19-5) pentanoic acid    [2-((S)-2-cyclohexyl-3-mercaptopropionylamino)ethyl][2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-6) pentanoic acid (2′-acetylsulfamoylbiphenyl-4-ylmethyl)    {2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-7) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl){2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-8) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl){2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}amide    (the synthesis of this compound is described in Example 8);-   (19-9) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoylbiphenyl-4-ylmethyl)pentanoylamino]ethyl}amide;-   (19-10) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl){2-[(S)-2-cyclohexyl-3-mercaptopropionylamino]ethyl}amide;-   (19-11) pentanoic acid    {2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-12) pentanoic acid    {2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-13) pentanoic acid    [2-((R)-2-benzyl-2-mercaptoethylcarbamoyl)ethyl][2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-14) pentanoic acid    [2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]amide;-   (19-15) pentanoic acid    [2-((R)-2-cyclohexyl-2-mercaptoethylcarbamoyl)ethyl][2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-16) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl){2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-17) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl){2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-18) pentanoic acid (2′-acetylsulfamoylbiphenyl-4-ylmethyl)    {2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-19) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl)-[2-((R)-1-mercaptomethyl-3-methyl-butylcarbamoyl)ethyl]amide;-   (19-20) pentanoic acid    (2′-acetylsulfamoylbiphenyl-4-ylmethyl){2-[(R)-2-cyclohexyl-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-21) pentanoic acid    {2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-22) pentanoic acid    {2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-23) pentanoic acid    {2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-24) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]pentanoylamino}ethyl)amide-   (19-25) pentanoic acid    {2-[(S)-2-cyclohexyl-3-mercaptopropionylamino]ethyl}[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-26) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-27) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-28) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-[2-((S)-2-benzyl-3-mercaptopropionylamino)ethyl]amide,    MS m/z: [M+H⁺] calcd for C₃₂H₃₈FN₃O₅S₂, 628.22. found 628.6. (this    compound was synthesized in a manner similar to that described in    Example 8);-   (19-29) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)pentanoylamino]ethyl}amide;-   (19-30) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)[2-((S)-2-cyclohexyl-3-mercaptopropionylamino)ethyl]amide;-   (19-31) pentanoic acid    {2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-32) pentanoic acid    {2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-33) pentanoic acid    {2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-34) pentanoic acid    [3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl][2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]amide;-   (19-35) pentanoic acid    {2-[(R)-2-cyclohexyl-2-mercaptoethylcarbamoyl]ethyl}-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amide;-   (19-36) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-37) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-38) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-[2-((R))-2-benzyl-2-mercaptoethylcarbamoyl)ethyl]amide;-   (19-39) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]amide;-   (19-40) pentanoic acid    (2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-[2-((R)-2-cyclohexyl-2-mercaptoethylcarbamoyl)ethyl]amide;-   (19-41) pentanoic acid    [2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-42) pentanoic acid    [2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-43) pentanoic acid    [2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]{2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}amide;-   (19-44) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]pentanoylamino}ethyl)amide;-   (19-45) pentanoic acid    [2-chloro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]-{2-[(S)-2-cyclohexyl-3-mercapto-propionylamino]ethyl}amide;-   (19-46) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)    {2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-47) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl){2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}amide;-   (19-48) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl){2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}amide;-   (19-49) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)pentanoylamino]ethyl}amide;-   (19-50) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl){2-[(S)-2-cyclohexyl-3-mercaptopropionylamino]ethyl}amide;-   (19-51) pentanoic acid    [2-chloro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-52) pentanoic acid    [2-chloro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-53) pentanoic acid    [2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-{2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-54) pentanoic acid    [2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl][2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]amide;-   (19-55) pentanoic acid    [2-chloro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]-{2-[(S)-2-cyclohexyl-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-56) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ymethyl)    {2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-57) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl){2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-58) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)    {2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}amide;-   (19-59) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]amide;    and-   (19-60) pentanoic acid    (2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl){2-[(R)-2-cyclohexyl-2-mercaptoethylcarbamoyl]ethyl}amide;    and pharmaceutically acceptable salts thereof.

Example 20

Following the procedures described in Examples above, and substitutingthe appropriate starting materials and reagents, compounds 20-1 to 20-27and 20-29 to 20-60, having the following formulas (20a), (20b), (20c),(20d), (20e), or (20f), can also be prepared. Compound 20-28 wassynthesized in a manner similar to that described in Example 8.

(20a)

(20b)

(20c)

(20d)

(20e)

(20f)

Ex. Formula R^(1d) R⁶ 20-1 20a —C(O)—CH(CH₃)OH -2-fluorobenzyl 20-2 20a—C(O)—CH(CH₃)OH -3-chlorobenzyl 20-3 20a —C(O)—CH(CH₃)OH benzyl 20-4 20a—C(O)—CH(CH₃)OH i-butyl 20-5 20a —C(O)—CH(CH₃)OH cyclohexyl 20-6 20a—C(O)CH₃ -2-fluorobenzyl 20-7 20a —C(O)CH₃ -3-chlorobenzyl 20-8 20a—C(O)CH₃ benzyl 20-9 20a —C(O)CH₃ i-butyl 20-10 20a —C(O)CH₃ cyclohexyl20-11 20b —C(O)—CH(CH₃)OH -2-fluorobenzyl 20-12 20b —C(O)—CH(CH₃)OH-3-chlorobenzyl 20-13 20b —C(O)—CH(CH₃)OH benzyl 20-14 20b—C(O)—CH(CH₃)OH i-butyl 20-15 20b —C(O)—CH(CH₃)OH cyclohexyl 20-16 20b—C(O)CH₃ -2-fluorobenzyl 20-17 20b —C(O)CH₃ -3-chlorobenzyl 20-18 20b—C(O)CH₃ benzyl 20-19 20b —C(O)CH₃ i-butyl 20-20 20b —C(O)CH₃ cyclohexyl20-21 20c —C(O)—CH(CH₃)OH -2-fluorobenzyl 20-22 20c —C(O)—CH(CH₃)OH-3-chlorobenzyl 20-23 20c —C(O)—CH(CH₃)OH benzyl 20-24 20c—C(O)—CH(CH₃)OH i-butyl 20-25 20c —C(O)—CH(CH₃)OH cyclohexyl 20-26 20c—C(O)CH₃ -2-fluorobenzyl 20-27 20c —C(O)CH₃ -3-chlorobenzyl 20-28 20c—C(O)CH₃ benzyl 20-29 20c —C(O)CH₃ i-butyl 20-30 20c —C(O)CH₃ cyclohexyl20-31 20d —C(O)—CH(CH₃)OH -2-fluorobenzyl 20-32 20d —C(O)—CH(CH₃)OH-3-chlorobenzyl 20-33 20d —C(O)—CH(CH₃)OH benzyl 20-34 20d—C(O)—CH(CH₃)OH i-butyl 20-35 20d —C(O)—CH(CH₃)OH cyclohexyl 20-36 20d—C(O)CH₃ -2-fluorobenzyl 20-37 20d —C(O)CH₃ -3-chlorobenzyl 20-38 20d—C(O)CH₃ benzyl 20-39 20d —C(O)CH₃ i-butyl 20-40 20d —C(O)CH₃ cyclohexyl20-41 20e —C(O)—CH(CH₃)OH -2-fluorobenzyl 20-42 20e —C(O)—CH(CH₃)OH-3-chlorobenzyl 20-43 20e —C(O)—CH(CH₃)OH benzyl 20-44 20e—C(O)—CH(CH₃)OH i-butyl 20-45 20e —C(O)—CH(CH₃)OH cyclohexyl 20-46 20e—C(O)CH₃ -2-fluorobenzyl 20-47 20e —C(O)CH₃ -3-chlorobenzyl 20-48 20e—C(O)CH₃ benzyl 20-49 20e —C(O)CH₃ i-butyl 20-50 20e —C(O)CH₃ cyclohexyl20-51 20f —C(O)—CH(CH₃)OH -2-fluorobenzyl 20-52 20f —C(O)—CH(CH₃)OH-3-chlorobenzyl 20-53 20f —C(O)—CH(CH₃)OH benzyl 20-54 20f—C(O)—CH(CH₃)OH i-butyl 20-55 20f —C(O)—CH(CH₃)OH cyclohexyl 20-56 20f—C(O)CH₃ -2-fluorobenzyl 20-57 20f —C(O)CH₃ -3-chlorobenzyl 20-58 20f—C(O)CH₃ benzyl 20-59 20f —C(O)CH₃ i-butyl 20-60 20f —C(O)CH₃ cyclohexyl

These compounds are named below. Although the nomenclature depicts onestereoisomer embodiment, it is understood that all stereoisomeric formsof these compounds are included in the invention.

-   (20-1)    N-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-2)    N-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-3)    N-[2-((S)-2-benzyl-3-mercaptopropionylamino)ethyl]-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-4) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{butyryl-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amino}ethyl)amide;-   (20-5)    N-[2-((S)-2-cyclohexyl-3-mercaptopropionylamino)ethyl]-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-6)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-7)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-8)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}butyramide;-   (20-9) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoylbiphenyl-4-ylmethyl)butyrylamino]ethyl}amide;-   (20-10)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(S)-2-cyclohexyl-3-mercaptopropionylamino]ethyl}butyramide;-   (20-11)    N-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-12)    N-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-13)    N-[2-((R)-2-benzyl-2-mercaptoethylcarbamoyl)ethyl]-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-14)    N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-[2-((R)-1-mercaptomethyl-3-methyl-butylcarbamoyl)ethyl]butyramide;-   (20-15)    N-[2-((R)-2-cyclohexyl-2-mercaptoethylcarbamoyl)ethyl]-N-[2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-16)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-17)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-18)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(R))-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-19)    N-(2′-acetylsulfamoylbiphenyl-4-ylmethyl)-N-[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]butyramide;-   (20-20)    N-(2′-acetylsulfamoyl-biphenyl-4-ylmethyl)-N-{2-[(R)-2-cyclohexyl-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-21)    N-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-22)    N-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-23)    N-{2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-24) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{butyryl-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amino}ethyl)amide;-   (20-25)    N-{2-[(S)-2-cyclohexyl)-3-mercaptopropionylamino]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-26)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-27)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-28)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-[2-((S)-2-benzyl-3-mercaptopropionylamino)ethyl]butyramide,    MS m/z: [M+H⁺] calcd for C₃₁H₃₆FN₃O₅S₂, 614.21. found 614.0. (this    compound was synthesized in a manner similar to that described in    Example 8);-   (20-29) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)butyrylamino]ethyl}amide;-   (20-30)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-[2-((S)-2-cyclohexyl-3-mercaptopropionylamino)ethyl]butyramide;-   (20-31)    N-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-32)    N-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-33)    N-{2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-34)    N-[3-fluoro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]butyramide;-   (20-35)    N-{2-[(R)-2-cyclohexyl)-2-mercaptoethylcarbamoyl]ethyl}-N-[3-fluoro-2′-((S)-2-hydroxy-propionylsulfamoyl)biphenyl-4-ylmethyl]butyramide;-   (20-36)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-{2-[(R))-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-37)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-38)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-[2-((R)-2-benzyl-2-mercaptoethylcarbamoyl)ethyl]butyramide;-   (20-39)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]butyramide;-   (20-40)    N-(2′-acetylsulfamoyl-3-fluorobiphenyl-4-ylmethyl)-N-[2-((R)-2-cyclohexyl-2-mercaptoethylcarbamoyl)ethyl]butyramide;-   (20-41)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-42)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-43)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}butyramide;-   (20-44) (S)-2-mercaptomethyl-4-methylpentanoic acid    (2-{butyryl-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]amino}ethyl)amide;-   (20-45)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(S)-2-cyclohexyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-46)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(S)-2-(2-fluorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-47)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(S)-2-(3-chlorobenzyl)-3-mercaptopropionylamino]ethyl}butyramide;-   (20-48)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(S)-2-benzyl-3-mercaptopropionylamino]ethyl}butyramide;-   (20-49) (S)-2-mercaptomethyl-4-methylpentanoic acid    {2-[(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)butyrylamino]ethyl}amide;-   (20-50)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(S)-2-cyclohexyl-3-mercaptopropionylamino]ethyl}butyramide;-   (20-51)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-52)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-53)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-54)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-[2-((R)-1-mercaptomethyl-3-methylbutylcarbamoyl)ethyl]butyramide;-   (20-55)    N-[2-chloro-2′-((S)-2-hydroxypropionylsulfamoyl)biphenyl-4-ylmethyl]-N-{2-[(R)-2-cyclohexyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-56)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(R)-2-(2-fluorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-57)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(R)-2-(3-chlorobenzyl)-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-58)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(R)-2-benzyl-2-mercaptoethylcarbamoyl]ethyl}butyramide;-   (20-59)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-[2-((R)-1-mercaptomethyl-3-methyl-butylcarbamoyl)ethyl]butyramide;    and-   (20-60)    N-(2′-acetylsulfamoyl-2-chlorobiphenyl-4-ylmethyl)-N-{2-[(R)-2-cyclohexyl-2-mercaptoethylcarbamoyl]ethyl}butyramide;    and pharmaceutically acceptable salts thereof.

Assay 1 AT₁ and AT₂ Radioligand Binding Assays

These in vitro assays were used to assess the ability of test compoundsto bind to the AT₁ and the AT₂ receptors.

Membrane Preparation from Cells Expressing Human AT₁ or AT₂ Receptors

Chinese hamster ovary (CHO-K1) derived cell lines stably expressing thecloned human AT₁ or AT₂ receptors, respectively, were grown in HAM's-F12medium supplemented with 10% fetal bovine serum, 10 μg/mlpenicillin/streptomycin, and 500 μg/ml geneticin in a 5% CO₂ humidifiedincubator at 37° C. AT₂ receptor expressing cells were grown in theadditional presence of 100 nM PD123,319 (AT₂ antagonist). When culturesreached 80-95% confluence, the cells were washed thoroughly in PBS andlifted with 5 mM EDTA. Cells were pelleted by centrifugation and snapfrozen in MeOH-dry ice and stored at −80° C. until further use.

For membrane preparation, cell pellets were resuspended in lysis buffer(25 mM Tris/HCl pH 7.5 at 4° C., 1 mM EDTA, and one tablet of CompleteProtease Inhibitor Cocktail Tablets with 2 mM EDTA per 50 mL buffer(Roche cat.#1697498, Roche Molecular Biochemicals, Indianapolis, Ind.))and homogenized using a tight-fitting Dounce glass homogenizer (10strokes) on ice. The homogenate was centrifuged at 1000×g, thesupernatant was collected and centrifuged at 20,000×g. The final pelletwas resuspended in membrane buffer (75 mM Tris/HCl pH 7.5, 12.5 mMMgCl₂, 0.3 mM EDTA, 1 mM EGTA, 250 mM sucrose at 4° C.) and homogenizedby extrusion through a 20 G gauge needle. Protein concentration of themembrane suspension was determined by the method described in Bradford(1976) Anal Biochem. 72:248-54. Membranes were snap frozen in MeOH-dryice and stored at −80° C. until further use.

Ligand Binding Assay to Determine Compound Affinities for the Human AT₁and AT₂ Angiotensin Receptors

Binding assays were performed in 96-well Acrowell filter plates (PallInc., cat.#5020) in a total assay volume of 100 μL with 0.2 μg membraneprotein for membranes containing the human AT₁ receptor, or 2 μgmembrane protein for membranes containing the human AT₂ receptor inassay buffer (50 mM Tris/HCl pH 7.5 at 20° C., 5 mM MgCl₂, 25 μM EDTA,0.025% BSA). Saturation binding studies for determination of K_(d)values of the ligand were done using N-terminally Europium-labeledangiotensin-II ([Eu]AngII,H—(Eu—N¹)-Ahx-Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-OH; PerkinElmer, Boston,Mass.) at 8 different concentrations ranging from 0.1 nM to 30 nM.Displacement assays for determination of pK_(i) values of test compoundswere done with [Eu]AngII at 2 nM and 11 different concentrations of drugranging from 1 μM to 10 μM. Drugs were dissolved to a concentration of 1mM in DMSO and from there serially diluted into assay buffer.Non-specific binding was determined in the presence of 10 μM unlabeledangiotensin-II. Assays were incubated for 120 minutes in the dark, atroom temperature or 37° C., and binding reactions were terminated byrapid filtration through the Acrowell filter plates followed by threewashes with 200 μL ice cold wash buffer (50 mM Tris/HCl pH 7.5 at 4° C.,5 mM MgCl₂) using a Waters filtration manifold. Plates were tapped dryand incubated with 50 μl DELFIA Enhancement Solution (PerkinElmercat.#4001-0010) at room temperature for 5 minutes on a shaker.Filter-bound [Eu]AngII was quantitated immediately on a Fusion platereader (PerkinElmer) using Time Resolved Fluorescence (TRF). Bindingdata were analyzed by nonlinear regression analysis with the GraphPadPrism Software package (GraphPad Software, Inc., San Diego, Calif.)using the 3-parameter model for one-site competition. The BOTTOM (curveminimum) was fixed to the value for nonspecific binding, as determinedin the presence of 10 μM angiotensin II. K_(i) values for drugs werecalculated from observed IC₅₀ values and the K_(d) value of [Eu]AngIIaccording to the Cheng-Prusoff equation described in Cheng et al. (1973)Biochem Pharmacol. 22(23):3099-108. Selectivities of test compounds forthe AT₁ receptor over the AT₂ receptor were calculated as the ratio ofAT₂K_(i)/AT₁K_(i). Binding affinities of test compounds were expressedas negative decadic logarithms of the K_(i) values (pK_(i)).

In this assay, a higher pK_(i) value indicates that the test compoundhas a higher binding affinity for the receptor tested. Exemplarycompounds of the invention that were tested in this assay, typicallywere found to have a pK_(i) at the AT₁ receptor greater than or equal toabout 5.0. For example, the compound of Example 1 was found to have apK_(i) value greater than about 7.0.

Assay 2 In Vitro Assays for the Quantitation of Inhibitor Potencies(IC₅₀) at Human and Rat NEP, and Human ACE

The inhibitory activities of compounds at human and rat NEP and humanACE were determined using in vitro assays as described below.

Extraction of NEP Activity from Rat Kidneys

Rat NEP was prepared from the kidneys of adult Sprague Dawley rats.Whole kidneys were washed in cold PBS and brought up in ice-cold lysisbuffer (1% Triton X-114, 150 mM NaCl, 50 mM Tris pH 7.5; Bordier (1981)J. Biol. Chem. 256:1604-1607) in a ratio of 5 mL of buffer for everygram of kidney. Samples were homogenized using a polytron hand heldtissue grinder on ice. Homogenates were centrifuged at 1000×g in aswinging bucket rotor for 5 minutes at 3° C. The pellet was resuspendedin 20 mL of ice cold lysis buffer and incubated on ice for 30 minutes.Samples (15-20 mL) were then layered onto 25 mL of ice-cold cushionbuffer (6% w/v sucrose, 50 mM pH 7.5 Tris, 150 mM NaCl, 0.06%, TritonX-114), heated to 37° C. for 3-5 minutes and centrifuged at 1000×g in aswinging bucket rotor at room temperature for 3 minutes. The two upperlayers were aspirated off, leaving a viscous oily precipitate containingthe enriched membrane fraction. Glycerol was added to a concentration of50% and samples were stored at −20° C. Protein concentrations werequantitated using a BCA detection system with BSA as a standard.

Enzyme Inhibition Assays

Recombinant human NEP and recombinant human ACE were obtainedcommercially (R&D Systems, Minneapolis, Minn., catalog numbers 1182-ZNand 929-ZN, respectively). The fluorogenic peptide substrate Mca-BK2(Mca-Arg-Pro-Pro-Gly-Phe-Ser-Ala-Phe-Lys(Dnp)-OH; Johnson et al. (2000)Anal. Biochem. 286: 112-118) was used for the human NEP and ACE assays,and Mca-RRL (Mca-DArg-Arg-Leu-(Dnp)-OH; Medeiros et al. (1997) Braz. J.Med. Biol. Res. 30:1157-1162) was used for the rat NEP assay (both fromAnaspec, San Jose, Calif.).

The assays were performed in 384-well white opaque plates at roomtemperature using the respective fluorogenic peptides at a concentrationof 10 μM in assay buffer (50 mM Tris/HCl at 25° C., 100 mM NaCl, 0.01%Tween-20, 1 μM Zn, 0.025% BSA). Human NEP and human ACE were used atconcentrations that resulted in quantitative proteolysis of 5 μM ofMca-BK2 within 20 minutes at room temperature. The rat NEP enzymepreparation was used at a concentration that yielded quantitativeproteolysis of 3 μM of Mca-RRL within 20 minutes at room temperature.

Assays were started by adding 25 μL of enzyme to 12.5 μL of testcompound at 12 concentrations (10 μM to 20 μM). Inhibitors were allowedto equilibrate with the enzyme for 10 minutes before 12.5 μL of thefluorogenic substrates were added to initiate the reaction. Reactionswere terminated by the addition of 10 μL of 3.6% glacial AcOH after 20minutes of incubation. Plates were read on a fluorometer with excitationand emission wavelengths set to 320 nm and 405 nm, respectively.

Raw data (relative fluorescence units) were normalized to % activityfrom the average high readings (no inhibition, 100% enzyme activity) andaverage low readings (full inhibition, highest inhibitor concentration,0% enzyme activity) using three standard NEP and ACE inhibitors,respectively. Nonlinear regression of the normalized data was performedusing a one site competition model (GraphPad Software, Inc., San Diego,Calif.). Data were reported as pIC₅₀ values.

Exemplary compounds of the invention that were tested in this assay,typically were found to have a pIC₅₀ for the NEP enzyme greater than orequal to about 5.0, for example, the compound of Example 1 has a pIC₅₀value greater than or equal to about 7.0.

Assay 3 Pharmacodynamic (PD) Assay for ACE, AT₁, and NEP Activity inAnesthetized Rats

Male, Sprague Dawley, normotensive rats are anesthetized with 120 mg/kg(i.p.) of inactin. Once anesthetized, the jugular vein, carotid artery(PE 50 tubing) and bladder (URI-1 urinary silicone catheter) arecannulated and a tracheotomy is performed (Teflon Needle, size 14 gauge)to facilitate spontaneous respiration. The animals are then allowed a 60minute stabilization period and kept continuously infused with 5 mL/kg/hof saline (0.9%) throughout, to keep them hydrated and ensure urineproduction. Body temperature is maintained throughout the experiment byuse of a heating pad. At the end of the 60 minute stabilization period,the animals are dosed intravenously (i.v.) with two doses of angiotensin(AngI, 1.0 μg/kg, for ACE inhibitor activity; AngII, 0.1 μg/kg, for AT₁receptor antagonist activity) at 15 minutes apart. At 15 minutespost-second dose of angiotensin (AngI or AngII), the animals are treatedwith vehicle or test compound. Five minutes later, the animals areadditionally treated with a bolus i.v. injection of atrial natriureticpeptide (ANP; 30 μg/kg). Urine collection (into pre-weighted eppendorftubes) is started immediately after the ANP treatment and continued for60 minutes. At 30 and 60 minutes into urine collection, the animals arere-challenged with angiotensin (AngI or AngII). Blood pressuremeasurements are done using the Notocord system (Kalamazoo, Mich.).Urine samples are frozen at −20° C. until used for the cGMP assay. UrinecGMP concentrations are determined by Enzyme Immuno Assay using acommercial kit (Assay Designs, Ann Arbor, Mich., Cat. No. 901-013).Urine volume is determined gravimetrically. Urinary cGMP output iscalculated as the product of urine output and urine cGMP concentration.ACE inhibition or AT₁ antagonism is assessed by quantifying the %inhibition of pressor response to AngI or AngII, respectively. NEPinhibition is assessed by quantifying the potentiation of ANP-inducedelevation in urinary cGMP output.

Assay 4

In Vivo Evaluation of Antihypertensive Effects in the Conscious SHRModel of Hypertension

Spontaneously hypertensive rats (SHR, 14-20 weeks of age) are allowed aminimum of 48 hours acclimation upon arrival at the testing site. Sevendays prior to testing, the animals are either placed on a restrictedlow-salt diet with food containing 0.1% of sodium for sodium depletedSHRs (SD-SHR) or are placed on a normal diet for sodium repleted SHRs(SR-SHR). Two days prior to testing, the animals are surgicallyimplemented with catheters into a carotid artery and the jugular vein(PE50 polyethylene tubing) connected via a PE10 polyethylene tubing to aselected silicone tubing (size 0.020 ID×0.037 OD×0.008 wall) for bloodpressure measurement and test compound delivery, respectively. Theanimals are allowed to recover with appropriate post operative care.

On the day of the experiment, the animals are placed in their cages andthe catheters are connected via a swivel to a calibrated pressuretransducer. After 1 hour of acclimation, a baseline measurement is takenover a period of at least five minutes. The animals are then dosed i.v.with vehicle or test compound in ascending cumulative doses every 60minutes followed by a 0.3 mL saline to clear the catheter after eachdose. Data is recorded continuously for the duration of the study usingNotocord software (Kalamazoo, Mich.) and stored as electronic digitalsignals. In some studies, the effects of a single intravenous or oral(gavage) dose are monitored for at least 6 hours after dosing.Parameters measured are blood pressure (systolic, diastolic and meanarterial pressure) and heart rate.

Assay 5 In Vivo Evaluation of Antihypertensive Effects in the ConsciousDOCA-Salt Rat Model of Hypertension

CD rats (male, adult, 200-300 grams, Charles River Laboratory, USA) areallowed a minimum of 48 hours acclimation upon arrival at the testingsite before they are placed on a high salt diet.

One week after the start of the high salt diet, a DOCA-salt pellet (100mg, 21 days release time, Innovative Research of America, Sarasota,Fla.) is implanted subcutaneously and unilateral nephrectomy isperformed. On 16 or 17 days post DOCA-salt pellet implantation, animalsare implanted surgically with catheters into a carotid artery and thejugular vein with a PE50 polyethylene tubing, which in turn wasconnected via a PE10 polyethylene tubing to a selected silicone tubing(size 0.020 ID×0.037 OD×0.008 wall) for blood pressure measurement andtest compound delivery, respectively. The animals are allowed to recoverwith appropriate post operative care.

On the day of the experiment, each animal is kept in its cage andconnected via a swivel to a calibrated pressure transducer. After 1 hourof acclimation, a baseline measurement is taken over a period of atleast five minutes. The animals are then dosed i.v. with a vehicle ortest compound in escalating cumulative doses every 60 minutes followedby 0.3 mL of saline to flush the catheter after each dose. In somestudies, the effects of a single intravenous or oral (gavage) dose istested and monitored for at least 6 hours after dosing. Data is recordedcontinuously for the duration of the study using Notocord software(Kalamazoo, Mich.) and stored as electronic digital signals. Parametersmeasured are blood pressure (systolic, diastolic and mean arterialpressure) and heart rate. For cumulative and single dosing, thepercentage change in mean arterial pressure (MAP, mmHg) or heart rate(HR, bpm) is determined as described for Assay 4.

While the present invention has been described with reference tospecific aspects or embodiments thereof, it will be understood by thoseof ordinary skilled in the art that various changes can be made orequivalents can be substituted without departing from the true spiritand scope of the invention. Additionally, to the extent permitted byapplicable patent statues and regulations, all publications, patents andpatent applications cited herein are hereby incorporated by reference intheir entirety to the same extent as if each document had beenindividually incorporated by reference herein.

1. A compound of formula I:

wherein: r is 0, 1 or 2; Ar is an aryl group selected from:

R¹ is selected from —COOR^(1a), —NHSO₂R^(1b), —SO₂NHR^(1d), —SO₂OH,—C(O)NH—SO₂R^(1c), —P(O)(OH)₂, —CN, —O—CH(R^(1e))—COOH, tetrazol-5-yl,

R^(1a) is H, —C₁₋₆alkyl, —C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl,—C₃₋₆cycloalkyl, —CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,

R^(1aa) is —O—C₁₋₆alkyl, —O-cycloalkyl, —NR^(1ab)R^(1ac), or—CH(NH₂)CH₂COOCH₃; R^(1ab) and R^(1ac) are independently selected fromH, —C₁₋₆alkyl, and benzyl, or are taken together as —(CH₂)₃₋₆—; R^(1b)is R^(1c) or —NHC(O)R^(1c); R^(1c) is —C₁₋₆alkyl,—C₀₋₆alkylene-O—R^(1ca), —C₁₋₅alkylene-NR^(1cb)R^(1cc), or—C₀₋₄alkylenearyl; R^(1ca) is H, —C₁₋₆alkyl, or—C₁₋₆alkylene-O—C₁₋₆alkyl; R^(1cb) and R^(1cc) are independentlyselected from H and —C₁₋₆alkyl, or are taken together as—(CH₂)₂—O—(CH₂)₂— or —(CH₂)₂—N[C(O)CH₃]-(CH₂)₂—; R^(1d) is H, R^(1c),—C(O)R^(1c), or —C(O)NHR^(1c); R^(1e) is —C₁₋₄alkyl or aryl; R³ isselected from —C₁₋₁₀alkyl, —C₂₋₁₀alkenyl, —C₃₋₁₀alkynyl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, —C₂₋₃alkenylene-C₃₋₇cycloalkyl,—C₂₋₃alkynylene-C₃₋₇cycloalkyl,—C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b),—C₀₋₅alkylene-O—C₀₋₅alkylene-R^(3b), —C₁₋₅alkylene-S—C₁₋₅alkylene-R^(3b)and —C₀₋₃alkylenearyl; R^(3a) is H, —C₁₋₆alkyl, —C₃₋₆cycloalkyl, or—C₀₋₃alkylenearyl; and R^(3b) is H, —C₁₋₆alkyl, —C₃₋₆cycloalkyl,—C₂₋₄alkenyl, —C₂₋₄alkynyl, or aryl; X is —C₁₋₁₂alkylene-, where atleast one —CH₂— moiety in the alkylene is replaced with a —NR^(4a)—C(O)—or —C(O)—NR^(4a)— moiety, where R^(4a) is selected from H, —OH, and—C₁₋₄alkyl; R⁵ is selected from —C₀₋₃alkylene-SR^(5a),—C₀₋₃alkylene-C(O)NR^(5b)R^(5c), and —C₀₋₃alkylene-NR^(5b)—C(O)R^(5d);where R^(5a) is H or —C(O)—R^(5aa); R^(5aa) is —C₁₋₆alkyl,—C₀₋₆alkylene-C₃₋₇cycloalkyl, —C₀₋₆alkylenearyl,—C₀₋₆alkyleneheteroaryl, —C₀₋₆alkylenemorpholine,—C₀₋₆alkylenepiperazine-CH₃, —CH(NH₂)-aa where aa is an amino acid sidechain, -2-pyrrolidine, —C₀₋₆alkylene-OR^(5ab), —OC₀₋₆alkylenearyl,—C₁₋₂alkylene-OC(O)—C₁₋₆alkyl, —C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, or—O—C₁₋₂alkylene- OC(O)—O—C₁₋₆alkyl; R^(5ab) is H or —C₁₋₆alkyl; R^(5b)is H, —OH, —OC(O)R^(5ba), —CH₂COOH, —O-benzyl, -pyridyl, or—OC(S)NR^(5bb)R^(5bc); R^(5ba) is —C₁₋₆alkyl, —OCH₂-aryl, —CH₂O-aryl, or—NR^(5bb)R^(5bc); R^(1bb) and R^(5bc) are independently selected from Hand —C₁₋₄alkyl; R^(5c) is H, —C₁₋₆alkyl, or —C(O)—R^(5ca); R^(5ca) is—C₁₋₆alkyl, —C₃₋₇cycloalkyl, aryl, or heteroaryl; R^(5d) is H,—C₁₋₄alkyl, —C₀₋₃alkylenearyl, —NR^(5da)R^(5db), —CH₂SH, or—O—C₁₋₆alkyl; R^(5da) and R^(5db) are independently selected from H and—C₁₋₄alkyl; R⁶ is selected from —C₁₋₆alkyl, —CH₂O(CH₂)₂OCH₃,—C₁₋₆alkylene-O—C₁₋₆alkyl, —C₀₋₃alkylenearyl, —C₀₋₃alkyleneheteroaryl,and —C₀₋₃alkylene-C₃₋₇cycloalkyl; and R⁷ is H or is taken together withR⁶ to form —C₃₋₈cycloalkyl; wherein: each —CH₂— group in —(CH₂)_(r)— isoptionally substituted with 1 or 2 substituents independently selectedfrom —C₁₋₄alkyl and fluoro; each carbon atom in X is optionallysubstituted with one or more R^(4b) groups and one —CH₂— moiety in X maybe replaced with a group selected from —C₄₋₈cycloalkylene-,—CR^(4d)═CH—, and —CH═CR^(4d)—; wherein R^(4b) is selected from—C₀₋₅alkylene-COOR^(4c), —C₁₋₆alkyl, —C₀₋₁alkylene-CONH₂,—C₁₋₂alkylene-OH, —C₀₋₃alkylene-C₃₋₇cycloalkyl, 1H-indol-3-yl, benzyl,and hydroxybenzyl, where R^(4c) is H or —C₁₋₄alkyl; and R^(4d) isselected from —CH₂-thiophene and phenyl; each alkyl and each aryl in R¹,R³, R^(4a-4d), and R⁵⁻⁶ is optionally substituted with 1 to 7 fluoroatoms; each ring in Ar and each aryl in R¹, R³, and R⁵⁻⁶ is optionallysubstituted with 1 to 3 substituents independently selected from —OH,—C₁₋₆alkyl, —C₂₋₄alkenyl, —C₂₋₄alkynyl, —CN, halo, —O—C₁₋₆alkyl,—S—C₁₋₆alkyl, —S(O)—C₁₋₆alkyl, —S(O)₂—C₁₋₄alkyl, -phenyl, —NO₂,—NH₂,—NH—C₁₋₆alkyl and —N(C₁₋₆alkyl)₂, wherein each alkyl, alkenyl andalkynyl is optionally substituted with 1 to 5 fluoro atoms; andpharmaceutically acceptable salts thereof.
 2. The compound of claim 1,wherein r is
 1. 3. The compound of claim 1, wherein Ar is an aryl groupselected from:


4. The compound of claim 1, wherein R¹ is selected from —COOR^(1a),—SO₂NHR^(1d), and tetrazol-5-yl.
 5. The compound of claim 4, whereinR^(1a) is H, R^(1d) is —C(O)R^(1c), and R^(1c) is —C₁₋₆alkyl.
 6. Thecompound of claim 4, wherein R¹ is —COOR^(1a) and R^(1a) is —C₁₋₆alkyl,—C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl, —C₃₋₆cycloalkyl,—CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,


7. The compound of claim 1, wherein R³ is selected from —C₁₋₁₀alkyl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, —C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b),—C₀₋₅alkylene-O—C₀₋₅alkylene-R^(3b), and —C₀₋₃alkylenearyl; where R^(3a)is H; and R^(3b) is selected from H, —C₁₋₆alkyl, and phenyl.
 8. Thecompound of claim 7, wherein R³ is —C₂₋₅alkyl.
 9. The compound of claim1, wherein X is —C₂₋₁₁alkylene- and 1, 2 or 3 —CH₂—moieties are replacedwith a —NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety.
 10. The compound ofclaim 9, wherein R^(4a) is H.
 11. The compound of claim 10, wherein X is—(CH₂)₂—NHC(O)— or —(CH₂)₂—C(O)NH—.
 12. The compound of claim 9, whereinone of the carbon atoms in X is substituted with an R^(4b) groupselected from —COOH and —C₁₋₆alkyl.
 13. The compound of claim 1, whereinR^(5a) and R^(5c) are H, R^(5b) is —OH, and R^(5d) is H or —CH₂SH. 14.The compound of claim 13, wherein R⁵ is selected from —C₀₋₁alkylene-SH,—C₀₋₁alkylene-C(O)N(OH)H, and —C₀₋₃alkylene-N(OH)—C(O)H.
 15. Thecompound of claim 13, wherein R¹ is selected from —COOR^(1a) whereR^(1a) is H, —SO₂NHR^(1d), and tetrazol-5-yl.
 16. The compound of claim13, wherein R¹ is —COOR^(1a) and R^(1a) is —C₁₋₆alkyl,—C₁₋₃alkylenearyl, —C₁₋₃alkyleneheteroaryl, —C₃₋₆cycloalkyl,—CH(C₁₋₄alkyl)OC(O)R^(1aa), —C₀₋₆alkylenemorpholine,


17. The compound of claim 13, wherein R^(5a) is selected from—C(O)—C₁₋₆alkyl, —C(O)—C₀₋₆alkylene-C₃₋₇cycloalkyl,—C(O)—C₀₋₆alkylenearyl, —C(O)—C₀₋₆alkyleneheteroaryl,—C(O)—C₀₋₆alkylenemorpholine, —C(O)—C₀₋₆alkylenepiperazine-CH₃,—C(O)—CH(NH₂)-aa where aa is an amino acid side chain,—C(O)-2-pyrrolidine, —C(O)—O—C₁₋₆alkyl, —C(O)—OC₀₋₆alkylenearyl,—C₁₋₂alkylene-OC(O)—C₁₋₆alkyl, —C₁₋₂alkylene-OC(O)—C₀₋₆alkylenearyl, and—O—C₁₋₂alkylene-OC(O)—O—C₁₋₆alkyl; and R^(5b) is selected from—OC(O)—C₁₋₆alkyl, —CH₂COOH, —O-benzyl, -pyridyl, —OC(O)OCH₂-phenyl,—OC(O)CH₂O-phenyl, —OC(O)N(CH₃)₂, and —OC(S)N(CH₃)₂.
 18. The compound ofclaim 17, wherein R¹ is selected from —COOR^(1a) where R^(1a) is H,—SO₂NHR^(1d), and tetrazol-5-yl.
 19. The compound of claim 17, whereinR¹ is —COOR^(1a) and R^(1a) is —C₁₋₆alkyl, —C₁₋₃alkylenearyl,—C₁₋₃alkyleneheteroaryl, —C₃₋₆cycloalkyl, —CH(C₁₋₄alkyl)OC(O)R^(1aa),—C₀₋₆alkylenemorpholine,


20. The compound of claim 1, wherein R⁶ is selected from —C₁₋₆alkyl,—C₀₋₃alkylenearyl, and —C₀₋₃alkylene-C₃₋₇cycloalkyl.
 21. The compound ofclaim 1, wherein R⁷ is H.
 22. The compound of claim 1, wherein Ar issubstituted with 1-2 halo groups.
 23. The compound of claim 1, havingformula Ia:


24. The compound of claim 23, having formula Ib:


25. The compound of claim 24, having formula Ic:


26. The compound of claim 23, where Ar is an aryl group selected from:

R¹ is selected from —COOR^(1a), —SO₂NHR^(1d), and tetrazol-5-yl; whereR^(1a) is selected from H and —C₁₋₆alkyl; R^(1d) is —C(O)R^(1c); andR^(1c) is —C₁₋₆alkyl; R³ is selected from —C₁₋₁₀alkyl,—C₀₋₃alkylene-C₃₋₇cycloalkyl, —C₀₋₅alkylene-NR^(3a)—C₀₋₅alkylene-R^(3b),—C₀₋₅alkylene-O-—C₀₋₅alkylene-R^(3b), and —C₀₋₃alkylenearyl; whereR^(3a) is H; and R^(3b) is selected from H, —C₁₋₆alkyl, and phenyl; X is—C₂₋₁₁alkylene-, where 1, 2 or 3 —CH₂— moieties are replaced with a—NR^(4a)—C(O)— or —C(O)—NR^(4a)— moiety, where R^(4a) is H; R⁵ isselected from —C₀₋₃alkylene-SR^(5a), —C₀₋₃alkylene-C(O)NR^(5b)R^(5c),and —C₀₋₁alkylene-NHC(O)CH₂SH; where R^(5a) is selected from H and—C(O)—C₁₋₆alkyl; R^(5b) is selected from —OH and —OC(O)—C₁₋₆alkyl; andR^(5c) is H; and R⁶ is selected from —C₁₋₆alkyl, —C₀₋₃alkylenearyl, and—C₀₋₃alkylene-C₃₋₇cycloalkyl; and each carbon atom in X is optionallysubstituted with one or two R^(4b) groups selected from—C₀₋₅alkylene-COOR^(4c) and —C₁₋₆alkyl, where R^(4c) is H.
 27. Thecompound of claim 26, where Ar is:

R¹ is selected from —SO₂NHR^(1d) and tetrazol-5-yl; where R^(1d) is—C(O)R^(1c) and R^(1c) is —C₁₋₆alkyl; R³ is selected from —C₂₋₅alkyl and—C₀₋₁alkylene-C₃₋₅cycloalkyl; X is —C₂₋₅alkylene-, where 1 or 2 —CH₂—moieties in the alkylene are replaced with a —NR^(4a)—C(O)— or—C(O)—NR^(4a)— moiety, where R^(4a) is H; R⁵ is selected from—C₀₋₃alkylene-SR^(5a) and —C₀₋₃alkylene-C(O)NR^(5b)R^(5c); R^(5a) is Hor —C(O)—C₁₋₆alkyl; R^(5b) is —OH or —OC(O)—C₁₋₆alkyl; and R^(5c) is H;and R⁶ is selected from —C₁₋₆alkyl, —C₀₋₃alkylenearyl, and—C₀₋₃alkylene-C₃₋₇cycloalkyl; and one carbon atom in X is optionallysubstituted with one R^(4b) group selected from —COOH and —C₁₋₃alkyl.28. The compound of claim 1, having formula Id:

wherein: R^(1d) is —C(O)R^(1c); R^(1c) is —C₁₋₆alkyl or—C₀₋₆alkylene-O—R^(1ca); R^(1ca) is H; R³ is —C₁₋₁₀alkyl; X is—(CH₂)₂—NHC(O)— or —(CH₂)₂—C(O)NH—; and R⁶ is selected from —C₁₋₆alkyl,—C₀₋₃alkylenearyl, and —C₀₋₃alkylene-C₃₋₇cycloalkyl.
 29. The compound ofclaim 28, wherein one ring in Ar and the aryl in R⁶ are optionallysubstituted with a halo group.
 30. The compound of claim 28, whereinR^(1d) is —C(O)CH₃ or —C(O)—CH(CH₃)OH; and R⁶ is i-butyl, benzyl,-2-fluorobenzyl, -3-chlorobenzyl, or cyclohexyl.
 31. An intermediateuseful in the synthesis of the compound of claim 1, selected from thegroup comprising:

where Ar* is Ar—R¹*; R¹* is selected from —C(O)O—P², —SO₂O—P⁵,—SO₂NH—P⁶, —P(O)(O—P⁷)₂, —OCH(CH₃)—C(O)O—P², —OCH(aryl)-C(O)O—P², andtetrazol-5-yl-P⁴; R⁵* is selected from —C₀₋₃alkylene-S—P³,—C₀₋₃alkylene-C(O)NH(O—P⁵), —C₀₋₃alkylene-N(O—P⁵)—C(O)R^(5d), and—C₀₋₁alkylene-NHC(O)CH₂S—P³, ; P² is a carboxy-protecting group; P³ is athiol-protecting group; P⁴ is a tetrazole-protecting group; P⁵ is ahydroxyl-protecting group; P⁶ is a sulfonamide-protecting group; andsalts thereof.
 32. A pharmaceutical composition comprising the compoundof claim 1 and a pharmaceutically acceptable carrier.
 33. Thecomposition of claim 32, further comprising a second therapeutic agent.34. The composition of claim 33, wherein the second therapeutic agent isselected from diuretics, β₁ adrenergic receptor blockers, calciumchannel blockers, angiotensin-converting enzyme inhibitors, AT₁ receptorantagonists, neprilysin inhibitors, non-steroidal anti-inflammatoryagents, prostaglandins, anti-lipid agents, anti-diabetic agents,anti-thrombotic agents, renin inhibitors, endothelin receptorantagonists, endothelin converting enzyme inhibitors, aldosteroneantagonists, angiotensin-converting enzyme/neprilysin inhibitors, andcombinations thereof.